feat: add models scan and fallbacks

docs/configuration.md

@@ -430,6 +430,7 @@ Controls the embedded agent runtime (model/thinking/verbose/timeouts).
 `allowedModels` lets `/model` list/filter and enforce a per-session allowlist
 (omit to show the full catalog).
 `modelAliases` adds short names for `/model` (alias -> provider/model).
+`modelFallbacks` lists ordered fallback models to try when the default fails.
 
 ```json5
 {
@@ -443,6 +444,10 @@ Controls the embedded agent runtime (model/thinking/verbose/timeouts).
       Opus: "anthropic/claude-opus-4-5",
       Sonnet: "anthropic/claude-sonnet-4-1"
     },
+    modelFallbacks: [
+      "openrouter/deepseek/deepseek-r1:free",
+      "openrouter/meta-llama/llama-3.3-70b-instruct:free"
+    ],
     thinkingDefault: "low",
     verboseDefault: "off",
     elevatedDefault: "on",

docs/models.md

@@ -12,18 +12,18 @@ that prefers tool-call + image-capable models and maintains ordered fallbacks.
 
 ## Command tree (draft)
 
-- `clawdis models list`
+- `clawdbot models list`
   - default: configured models only
   - flags: `--all` (full catalog), `--local`, `--provider <name>`, `--json`, `--plain`
-- `clawdis models status`
+- `clawdbot models status`
-  - show default model + last used + aliases + fallbacks
+  - show default model + aliases + fallbacks + allowlist
-- `clawdis models set <modelOrAlias>`
+- `clawdbot models set <modelOrAlias>`
   - writes `agent.model` in config
-- `clawdis models aliases list|add|remove`
+- `clawdbot models aliases list|add|remove`
   - writes `agent.modelAliases`
-- `clawdis models fallbacks list|add|remove|clear`
+- `clawdbot models fallbacks list|add|remove|clear`
   - writes `agent.modelFallbacks`
-- `clawdis models scan`
+- `clawdbot models scan`
   - OpenRouter :free scan; probe tool-call + image; interactive selection
 
 ## Config changes
@@ -38,7 +38,9 @@ that prefers tool-call + image-capable models and maintains ordered fallbacks.
 
 Input
 - OpenRouter `/models` list (filter `:free`)
+- Requires `OPENROUTER_API_KEY` (or stored OpenRouter key in auth storage)
 - Optional filters: `--max-age-days`, `--min-params`, `--provider`, `--max-candidates`
+- Probe controls: `--timeout`, `--concurrency`
 
 Probes (direct pi-ai complete)
 - Tool-call probe (required):
@@ -49,13 +51,13 @@ Probes (direct pi-ai complete)
 Scoring/selection
 - Prefer models passing tool + image.
 - Fallback to tool-only if no tool+image pass.
-- Rank by: tool+image first, then lower median latency, then larger context.
+- Rank by: image ok, then lower tool latency, then larger context, then params.
 
 Interactive selection (TTY)
 - Multiselect list with per-model stats:
   - model id, tool ok, image ok, median latency, context, inferred params.
 - Pre-select top N (default 6).
-- Non-TTY: auto-select; require `--yes` or use defaults.
+- Non-TTY: auto-select; require `--yes`/`--no-input` to apply.
 
 Output
 - Writes `agent.modelFallbacks` ordered.
@@ -64,6 +66,7 @@ Output
 ## Runtime fallback
 
 - On model failure: try `agent.modelFallbacks` in order.
+- Ignore fallback entries not in `agent.allowedModels` (if allowlist set).
 - Persist last successful provider/model to session entry.
 - `/status` shows last used model (not just default).
 

src/agents/model-fallback.ts

@@ -0,0 +1,150 @@
+import type { ClawdbotConfig } from "../config/config.js";
+import { DEFAULT_MODEL, DEFAULT_PROVIDER } from "./defaults.js";
+import {
+  buildModelAliasIndex,
+  modelKey,
+  parseModelRef,
+  resolveModelRefFromString,
+} from "./model-selection.js";
+
+type ModelCandidate = {
+  provider: string;
+  model: string;
+};
+
+type FallbackAttempt = {
+  provider: string;
+  model: string;
+  error: string;
+};
+
+function isAbortError(err: unknown): boolean {
+  if (!err || typeof err !== "object") return false;
+  const name = "name" in err ? String(err.name) : "";
+  if (name === "AbortError") return true;
+  const message =
+    "message" in err && typeof err.message === "string"
+      ? err.message.toLowerCase()
+      : "";
+  return message.includes("aborted");
+}
+
+function buildAllowedModelKeys(
+  cfg: ClawdbotConfig | undefined,
+  defaultProvider: string,
+): Set<string> | null {
+  const rawAllowlist = cfg?.agent?.allowedModels ?? [];
+  if (rawAllowlist.length === 0) return null;
+  const keys = new Set<string>();
+  for (const raw of rawAllowlist) {
+    const parsed = parseModelRef(String(raw ?? ""), defaultProvider);
+    if (!parsed) continue;
+    keys.add(modelKey(parsed.provider, parsed.model));
+  }
+  return keys.size > 0 ? keys : null;
+}
+
+function resolveFallbackCandidates(params: {
+  cfg: ClawdbotConfig | undefined;
+  provider: string;
+  model: string;
+}): ModelCandidate[] {
+  const provider = params.provider.trim() || DEFAULT_PROVIDER;
+  const model = params.model.trim() || DEFAULT_MODEL;
+  const aliasIndex = buildModelAliasIndex({
+    cfg: params.cfg ?? {},
+    defaultProvider: DEFAULT_PROVIDER,
+  });
+  const allowlist = buildAllowedModelKeys(params.cfg, DEFAULT_PROVIDER);
+  const seen = new Set<string>();
+  const candidates: ModelCandidate[] = [];
+
+  const addCandidate = (candidate: ModelCandidate, enforceAllowlist: boolean) => {
+    if (!candidate.provider || !candidate.model) return;
+    const key = modelKey(candidate.provider, candidate.model);
+    if (seen.has(key)) return;
+    if (enforceAllowlist && allowlist && !allowlist.has(key)) return;
+    seen.add(key);
+    candidates.push(candidate);
+  };
+
+  addCandidate({ provider, model }, false);
+
+  for (const raw of params.cfg?.agent?.modelFallbacks ?? []) {
+    const resolved = resolveModelRefFromString({
+      raw: String(raw ?? ""),
+      defaultProvider: DEFAULT_PROVIDER,
+      aliasIndex,
+    });
+    if (!resolved) continue;
+    addCandidate(resolved.ref, true);
+  }
+
+  return candidates;
+}
+
+export async function runWithModelFallback<T>(params: {
+  cfg: ClawdbotConfig | undefined;
+  provider: string;
+  model: string;
+  run: (provider: string, model: string) => Promise<T>;
+  onError?: (attempt: {
+    provider: string;
+    model: string;
+    error: unknown;
+    attempt: number;
+    total: number;
+  }) => void | Promise<void>;
+}): Promise<{
+  result: T;
+  provider: string;
+  model: string;
+  attempts: FallbackAttempt[];
+}> {
+  const candidates = resolveFallbackCandidates(params);
+  const attempts: FallbackAttempt[] = [];
+  let lastError: unknown;
+
+  for (let i = 0; i < candidates.length; i += 1) {
+    const candidate = candidates[i] as ModelCandidate;
+    try {
+      const result = await params.run(candidate.provider, candidate.model);
+      return {
+        result,
+        provider: candidate.provider,
+        model: candidate.model,
+        attempts,
+      };
+    } catch (err) {
+      if (isAbortError(err)) throw err;
+      lastError = err;
+      attempts.push({
+        provider: candidate.provider,
+        model: candidate.model,
+        error: err instanceof Error ? err.message : String(err),
+      });
+      await params.onError?.({
+        provider: candidate.provider,
+        model: candidate.model,
+        error: err,
+        attempt: i + 1,
+        total: candidates.length,
+      });
+    }
+  }
+
+  if (attempts.length <= 1 && lastError) throw lastError;
+  const summary =
+    attempts.length > 0
+      ? attempts
+          .map(
+            (attempt) =>
+              `${attempt.provider}/${attempt.model}: ${attempt.error}`,
+          )
+          .join(" | ")
+      : "unknown";
+  throw new Error(
+    `All models failed (${attempts.length || candidates.length}): ${summary}`,
+    { cause: lastError instanceof Error ? lastError : undefined },
+  );
+}

src/agents/model-scan.ts

@@ -0,0 +1,379 @@
+import { Type } from "@sinclair/typebox";
+import {
+  complete,
+  getEnvApiKey,
+  getModel,
+  type Context,
+  type Model,
+  type Tool,
+  type OpenAICompletionsOptions,
+} from "@mariozechner/pi-ai";
+
+const OPENROUTER_MODELS_URL = "https://openrouter.ai/api/v1/models";
+const DEFAULT_TIMEOUT_MS = 12_000;
+const DEFAULT_CONCURRENCY = 3;
+
+const BASE_IMAGE_PNG =
+  "iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAQAAAC1HAwCAAAAC0lEQVR42mP8/x8AAwMCAO+X3mIAAAAASUVORK5CYII=";
+
+const TOOL_PING: Tool = {
+  name: "ping",
+  description: "Return OK.",
+  parameters: Type.Object({}),
+};
+
+type OpenRouterModelMeta = {
+  id: string;
+  name: string;
+  contextLength: number | null;
+  maxCompletionTokens: number | null;
+  supportedParametersCount: number;
+  modality: string | null;
+  inferredParamB: number | null;
+  createdAtMs: number | null;
+};
+
+export type ProbeResult = {
+  ok: boolean;
+  latencyMs: number | null;
+  error?: string;
+  skipped?: boolean;
+};
+
+export type ModelScanResult = {
+  id: string;
+  name: string;
+  provider: string;
+  modelRef: string;
+  contextLength: number | null;
+  maxCompletionTokens: number | null;
+  supportedParametersCount: number;
+  modality: string | null;
+  inferredParamB: number | null;
+  createdAtMs: number | null;
+  tool: ProbeResult;
+  image: ProbeResult;
+};
+
+export type OpenRouterScanOptions = {
+  apiKey?: string;
+  fetchImpl?: typeof fetch;
+  timeoutMs?: number;
+  concurrency?: number;
+  minParamB?: number;
+  maxAgeDays?: number;
+  providerFilter?: string;
+};
+
+type OpenAIModel = Model<"openai-completions">;
+
+function normalizeCreatedAtMs(value: unknown): number | null {
+  if (typeof value !== "number" || !Number.isFinite(value)) return null;
+  if (value <= 0) return null;
+  if (value > 1e12) return Math.round(value);
+  return Math.round(value * 1000);
+}
+
+function inferParamBFromIdOrName(text: string): number | null {
+  const raw = text.toLowerCase();
+  const matches = raw.matchAll(
+    /(?:^|[^a-z0-9])[a-z]?(\d+(?:\.\d+)?)b(?:[^a-z0-9]|$)/g,
+  );
+  let best: number | null = null;
+  for (const match of matches) {
+    const numRaw = match[1];
+    if (!numRaw) continue;
+    const value = Number(numRaw);
+    if (!Number.isFinite(value) || value <= 0) continue;
+    if (best === null || value > best) best = value;
+  }
+  return best;
+}
+
+function parseModality(modality: string | null): Array<"text" | "image"> {
+  if (!modality) return ["text"];
+  const normalized = modality.toLowerCase();
+  const parts = normalized.split(/[^a-z]+/).filter(Boolean);
+  const hasImage = parts.includes("image");
+  return hasImage ? ["text", "image"] : ["text"];
+}
+
+async function withTimeout<T>(
+  timeoutMs: number,
+  fn: (signal: AbortSignal) => Promise<T>,
+): Promise<T> {
+  const controller = new AbortController();
+  const timer = setTimeout(() => controller.abort(), timeoutMs);
+  try {
+    return await fn(controller.signal);
+  } finally {
+    clearTimeout(timer);
+  }
+}
+
+async function fetchOpenRouterModels(
+  fetchImpl: typeof fetch,
+): Promise<OpenRouterModelMeta[]> {
+  const res = await fetchImpl(OPENROUTER_MODELS_URL, {
+    headers: { Accept: "application/json" },
+  });
+  if (!res.ok) {
+    throw new Error(`OpenRouter /models failed: HTTP ${res.status}`);
+  }
+  const payload = (await res.json()) as { data?: unknown };
+  const entries = Array.isArray(payload.data) ? payload.data : [];
+
+  return entries
+    .map((entry) => {
+      if (!entry || typeof entry !== "object") return null;
+      const obj = entry as Record<string, unknown>;
+      const id = typeof obj.id === "string" ? obj.id.trim() : "";
+      if (!id) return null;
+      const name =
+        typeof obj.name === "string" && obj.name.trim()
+          ? obj.name.trim()
+          : id;
+
+      const contextLength =
+        typeof obj.context_length === "number" &&
+        Number.isFinite(obj.context_length)
+          ? obj.context_length
+          : null;
+
+      const maxCompletionTokens =
+        typeof obj.max_completion_tokens === "number" &&
+        Number.isFinite(obj.max_completion_tokens)
+          ? obj.max_completion_tokens
+          : typeof obj.max_output_tokens === "number" &&
+              Number.isFinite(obj.max_output_tokens)
+            ? obj.max_output_tokens
+            : null;
+
+      const supportedParametersCount = Array.isArray(obj.supported_parameters)
+        ? obj.supported_parameters.length
+        : 0;
+
+      const modality =
+        typeof obj.modality === "string" && obj.modality.trim()
+          ? obj.modality.trim()
+          : null;
+
+      const inferredParamB = inferParamBFromIdOrName(`${id} ${name}`);
+      const createdAtMs = normalizeCreatedAtMs(obj.created_at);
+
+      return {
+        id,
+        name,
+        contextLength,
+        maxCompletionTokens,
+        supportedParametersCount,
+        modality,
+        inferredParamB,
+        createdAtMs,
+      } satisfies OpenRouterModelMeta;
+    })
+    .filter((entry): entry is OpenRouterModelMeta => Boolean(entry));
+}
+
+async function probeTool(
+  model: OpenAIModel,
+  apiKey: string,
+  timeoutMs: number,
+): Promise<ProbeResult> {
+  const context: Context = {
+    messages: [
+      {
+        role: "user",
+        content: "Call the ping tool with {} and nothing else.",
+        timestamp: Date.now(),
+      },
+    ],
+    tools: [TOOL_PING],
+  };
+  const startedAt = Date.now();
+  try {
+    const message = await withTimeout(timeoutMs, (signal) =>
+      complete(model, context, {
+        apiKey,
+        maxTokens: 32,
+        temperature: 0,
+        toolChoice: "required",
+        signal,
+      } satisfies OpenAICompletionsOptions),
+    );
+
+    const hasToolCall = message.content.some(
+      (block) => block.type === "toolCall",
+    );
+    if (!hasToolCall) {
+      return {
+        ok: false,
+        latencyMs: Date.now() - startedAt,
+        error: "No tool call returned",
+      };
+    }
+
+    return { ok: true, latencyMs: Date.now() - startedAt };
+  } catch (err) {
+    return {
+      ok: false,
+      latencyMs: Date.now() - startedAt,
+      error: err instanceof Error ? err.message : String(err),
+    };
+  }
+}
+
+async function probeImage(
+  model: OpenAIModel,
+  apiKey: string,
+  timeoutMs: number,
+): Promise<ProbeResult> {
+  const context: Context = {
+    messages: [
+      {
+        role: "user",
+        content: [
+          { type: "text", text: "Reply with OK." },
+          { type: "image", data: BASE_IMAGE_PNG, mimeType: "image/png" },
+        ],
+        timestamp: Date.now(),
+      },
+    ],
+  };
+  const startedAt = Date.now();
+  try {
+    await withTimeout(timeoutMs, (signal) =>
+      complete(model, context, {
+        apiKey,
+        maxTokens: 16,
+        temperature: 0,
+        signal,
+      } satisfies OpenAICompletionsOptions),
+    );
+    return { ok: true, latencyMs: Date.now() - startedAt };
+  } catch (err) {
+    return {
+      ok: false,
+      latencyMs: Date.now() - startedAt,
+      error: err instanceof Error ? err.message : String(err),
+    };
+  }
+}
+
+function ensureImageInput(model: OpenAIModel): OpenAIModel {
+  if (model.input.includes("image")) return model;
+  return {
+    ...model,
+    input: Array.from(new Set([...model.input, "image"])),
+  };
+}
+
+async function mapWithConcurrency<T, R>(
+  items: T[],
+  concurrency: number,
+  fn: (item: T, index: number) => Promise<R>,
+): Promise<R[]> {
+  const limit = Math.max(1, Math.floor(concurrency));
+  const results: R[] = new Array(items.length);
+  let nextIndex = 0;
+
+  const worker = async () => {
+    while (true) {
+      const current = nextIndex;
+      nextIndex += 1;
+      if (current >= items.length) return;
+      results[current] = await fn(items[current] as T, current);
+    }
+  };
+
+  await Promise.all(
+    Array.from({ length: Math.min(limit, items.length) }, () => worker()),
+  );
+  return results;
+}
+
+export async function scanOpenRouterModels(
+  options: OpenRouterScanOptions = {},
+): Promise<ModelScanResult[]> {
+  const fetchImpl = options.fetchImpl ?? fetch;
+  const apiKey =
+    options.apiKey?.trim() || getEnvApiKey("openrouter") || "";
+  if (!apiKey) {
+    throw new Error(
+      "Missing OpenRouter API key. Set OPENROUTER_API_KEY to run models scan.",
+    );
+  }
+
+  const timeoutMs = Math.max(
+    1,
+    Math.floor(options.timeoutMs ?? DEFAULT_TIMEOUT_MS),
+  );
+  const concurrency = Math.max(
+    1,
+    Math.floor(options.concurrency ?? DEFAULT_CONCURRENCY),
+  );
+  const minParamB = Math.max(0, Math.floor(options.minParamB ?? 0));
+  const maxAgeDays = Math.max(0, Math.floor(options.maxAgeDays ?? 0));
+  const providerFilter = options.providerFilter?.trim().toLowerCase() ?? "";
+
+  const catalog = await fetchOpenRouterModels(fetchImpl);
+  const now = Date.now();
+
+  const filtered = catalog.filter((entry) => {
+    if (!entry.id.endsWith(":free")) return false;
+    if (providerFilter) {
+      const prefix = entry.id.split("/")[0]?.toLowerCase() ?? "";
+      if (prefix !== providerFilter) return false;
+    }
+    if (minParamB > 0) {
+      const params = entry.inferredParamB ?? 0;
+      if (params < minParamB) return false;
+    }
+    if (maxAgeDays > 0 && entry.createdAtMs) {
+      const ageMs = now - entry.createdAtMs;
+      const ageDays = ageMs / (24 * 60 * 60 * 1000);
+      if (ageDays > maxAgeDays) return false;
+    }
+    return true;
+  });
+
+  const baseModel = getModel(
+    "openrouter",
+    "openrouter/auto",
+  ) as OpenAIModel;
+
+  return mapWithConcurrency(filtered, concurrency, async (entry) => {
+    const model: OpenAIModel = {
+      ...baseModel,
+      id: entry.id,
+      name: entry.name || entry.id,
+      contextWindow: entry.contextLength ?? baseModel.contextWindow,
+      maxTokens: entry.maxCompletionTokens ?? baseModel.maxTokens,
+      input: parseModality(entry.modality),
+      reasoning: baseModel.reasoning,
+    };
+
+    const toolResult = await probeTool(model, apiKey, timeoutMs);
+    const imageResult = toolResult.ok
+      ? await probeImage(ensureImageInput(model), apiKey, timeoutMs)
+      : { ok: false, latencyMs: null, skipped: true };
+
+    return {
+      id: entry.id,
+      name: entry.name,
+      provider: "openrouter",
+      modelRef: `openrouter/${entry.id}`,
+      contextLength: entry.contextLength,
+      maxCompletionTokens: entry.maxCompletionTokens,
+      supportedParametersCount: entry.supportedParametersCount,
+      modality: entry.modality,
+      inferredParamB: entry.inferredParamB,
+      createdAtMs: entry.createdAtMs,
+      tool: toolResult,
+      image: imageResult,
+    } satisfies ModelScanResult;
+  });
+}
+
+export { OPENROUTER_MODELS_URL };
+export type { OpenRouterModelMeta };

src/auto-reply/reply/agent-runner.ts

@@ -5,6 +5,7 @@ import {
   queueEmbeddedPiMessage,
   runEmbeddedPiAgent,
 } from "../../agents/pi-embedded.js";
+import { runWithModelFallback } from "../../agents/model-fallback.js";
 import {
   loadSessionStore,
   type SessionEntry,
@@ -170,8 +171,15 @@ export async function runReplyAgent(params: {
       registerAgentRunContext(runId, { sessionKey });
     }
     let runResult: Awaited<ReturnType<typeof runEmbeddedPiAgent>>;
+    let fallbackProvider = followupRun.run.provider;
+    let fallbackModel = followupRun.run.model;
     try {
-      runResult = await runEmbeddedPiAgent({
+      const fallbackResult = await runWithModelFallback({
+        cfg: followupRun.run.config,
+        provider: followupRun.run.provider,
+        model: followupRun.run.model,
+        run: (provider, model) =>
+          runEmbeddedPiAgent({
             sessionId: followupRun.run.sessionId,
             sessionKey,
             surface: sessionCtx.Surface?.trim().toLowerCase() || undefined,
@@ -183,8 +191,8 @@ export async function runReplyAgent(params: {
             extraSystemPrompt: followupRun.run.extraSystemPrompt,
             ownerNumbers: followupRun.run.ownerNumbers,
             enforceFinalTag: followupRun.run.enforceFinalTag,
-        provider: followupRun.run.provider,
+            provider,
-        model: followupRun.run.model,
+            model,
             thinkLevel: followupRun.run.thinkLevel,
             verboseLevel: followupRun.run.verboseLevel,
             bashElevated: followupRun.run.bashElevated,
@@ -196,7 +204,9 @@ export async function runReplyAgent(params: {
               ? async (payload) => {
                   let text = payload.text;
                   if (!opts?.isHeartbeat && text?.includes("HEARTBEAT_OK")) {
-                const stripped = stripHeartbeatToken(text, { mode: "message" });
+                    const stripped = stripHeartbeatToken(text, {
+                      mode: "message",
+                    });
                     if (stripped.didStrip && !didLogHeartbeatStrip) {
                       didLogHeartbeatStrip = true;
                       logVerbose("Stripped stray HEARTBEAT_OK token from reply");
@@ -226,7 +236,9 @@ export async function runReplyAgent(params: {
                       });
                       if (stripped.didStrip && !didLogHeartbeatStrip) {
                         didLogHeartbeatStrip = true;
-                    logVerbose("Stripped stray HEARTBEAT_OK token from reply");
+                        logVerbose(
+                          "Stripped stray HEARTBEAT_OK token from reply",
+                        );
                       }
                       const hasMedia = (payload.mediaUrls?.length ?? 0) > 0;
                       if (stripped.shouldSkip && !hasMedia) return;
@@ -239,7 +251,8 @@ export async function runReplyAgent(params: {
                     const cleaned = tagResult.cleaned || undefined;
                     const hasMedia = (payload.mediaUrls?.length ?? 0) > 0;
                     if (!cleaned && !hasMedia) return;
-                if (cleaned?.trim() === SILENT_REPLY_TOKEN && !hasMedia) return;
+                    if (cleaned?.trim() === SILENT_REPLY_TOKEN && !hasMedia)
+                      return;
                     const blockPayload: ReplyPayload = {
                       text: cleaned,
                       mediaUrls: payload.mediaUrls,
@@ -263,7 +276,9 @@ export async function runReplyAgent(params: {
                         didStreamBlockReply = true;
                       })
                       .catch((err) => {
-                    logVerbose(`block reply delivery failed: ${String(err)}`);
+                        logVerbose(
+                          `block reply delivery failed: ${String(err)}`,
+                        );
                       })
                       .finally(() => {
                         pendingStreamedPayloadKeys.delete(payloadKey);
@@ -277,7 +292,9 @@ export async function runReplyAgent(params: {
               ? async (payload) => {
                   let text = payload.text;
                   if (!opts?.isHeartbeat && text?.includes("HEARTBEAT_OK")) {
-                const stripped = stripHeartbeatToken(text, { mode: "message" });
+                    const stripped = stripHeartbeatToken(text, {
+                      mode: "message",
+                    });
                     if (stripped.didStrip && !didLogHeartbeatStrip) {
                       didLogHeartbeatStrip = true;
                       logVerbose("Stripped stray HEARTBEAT_OK token from reply");
@@ -291,10 +308,17 @@ export async function runReplyAgent(params: {
                     text = stripped.text;
                   }
                   await typing.startTypingOnText(text);
-              await opts.onToolResult?.({ text, mediaUrls: payload.mediaUrls });
+                  await opts.onToolResult?.({
+                    text,
+                    mediaUrls: payload.mediaUrls,
+                  });
                 }
               : undefined,
+          }),
       });
+      runResult = fallbackResult.result;
+      fallbackProvider = fallbackResult.provider;
+      fallbackModel = fallbackResult.model;
     } catch (err) {
       const message = err instanceof Error ? err.message : String(err);
       const isContextOverflow =
@@ -388,7 +412,12 @@ export async function runReplyAgent(params: {
 
     if (sessionStore && sessionKey) {
       const usage = runResult.meta.agentMeta?.usage;
-      const modelUsed = runResult.meta.agentMeta?.model ?? defaultModel;
+      const modelUsed =
+        runResult.meta.agentMeta?.model ?? fallbackModel ?? defaultModel;
+      const providerUsed =
+        runResult.meta.agentMeta?.provider ??
+        fallbackProvider ??
+        followupRun.run.provider;
       const contextTokensUsed =
         agentCfgContextTokens ??
         lookupContextTokens(modelUsed) ??
@@ -408,6 +437,7 @@ export async function runReplyAgent(params: {
             outputTokens: output,
             totalTokens:
               promptTokens > 0 ? promptTokens : (usage.total ?? input),
+            modelProvider: providerUsed,
             model: modelUsed,
             contextTokens: contextTokensUsed ?? entry.contextTokens,
             updatedAt: Date.now(),
@@ -422,6 +452,7 @@ export async function runReplyAgent(params: {
         if (entry) {
           sessionStore[sessionKey] = {
             ...entry,
+            modelProvider: providerUsed ?? entry.modelProvider,
             model: modelUsed ?? entry.model,
             contextTokens: contextTokensUsed ?? entry.contextTokens,
           };

src/auto-reply/reply/followup-runner.ts

@@ -1,6 +1,7 @@
 import crypto from "node:crypto";
 import { lookupContextTokens } from "../../agents/context.js";
 import { DEFAULT_CONTEXT_TOKENS } from "../../agents/defaults.js";
+import { runWithModelFallback } from "../../agents/model-fallback.js";
 import { runEmbeddedPiAgent } from "../../agents/pi-embedded.js";
 import { type SessionEntry, saveSessionStore } from "../../config/sessions.js";
 import { logVerbose } from "../../globals.js";
@@ -61,8 +62,15 @@ export function createFollowupRunner(params: {
       registerAgentRunContext(runId, { sessionKey: queued.run.sessionKey });
     }
     let runResult: Awaited<ReturnType<typeof runEmbeddedPiAgent>>;
+    let fallbackProvider = queued.run.provider;
+    let fallbackModel = queued.run.model;
     try {
-      runResult = await runEmbeddedPiAgent({
+      const fallbackResult = await runWithModelFallback({
+        cfg: queued.run.config,
+        provider: queued.run.provider,
+        model: queued.run.model,
+        run: (provider, model) =>
+          runEmbeddedPiAgent({
             sessionId: queued.run.sessionId,
             sessionKey: queued.run.sessionKey,
             surface: queued.run.surface,
@@ -74,15 +82,19 @@ export function createFollowupRunner(params: {
             extraSystemPrompt: queued.run.extraSystemPrompt,
             ownerNumbers: queued.run.ownerNumbers,
             enforceFinalTag: queued.run.enforceFinalTag,
-        provider: queued.run.provider,
+            provider,
-        model: queued.run.model,
+            model,
             thinkLevel: queued.run.thinkLevel,
             verboseLevel: queued.run.verboseLevel,
             bashElevated: queued.run.bashElevated,
             timeoutMs: queued.run.timeoutMs,
             runId,
             blockReplyBreak: queued.run.blockReplyBreak,
+          }),
       });
+      runResult = fallbackResult.result;
+      fallbackProvider = fallbackResult.provider;
+      fallbackModel = fallbackResult.model;
     } catch (err) {
       const message = err instanceof Error ? err.message : String(err);
       defaultRuntime.error?.(`Followup agent failed before reply: ${message}`);
@@ -121,7 +133,8 @@ export function createFollowupRunner(params: {
 
     if (sessionStore && sessionKey) {
       const usage = runResult.meta.agentMeta?.usage;
-      const modelUsed = runResult.meta.agentMeta?.model ?? defaultModel;
+      const modelUsed =
+        runResult.meta.agentMeta?.model ?? fallbackModel ?? defaultModel;
       const contextTokensUsed =
         agentCfgContextTokens ??
         lookupContextTokens(modelUsed) ??
@@ -141,6 +154,7 @@ export function createFollowupRunner(params: {
             outputTokens: output,
             totalTokens:
               promptTokens > 0 ? promptTokens : (usage.total ?? input),
+            modelProvider: fallbackProvider ?? entry.modelProvider,
             model: modelUsed,
             contextTokens: contextTokensUsed ?? entry.contextTokens,
             updatedAt: Date.now(),
@@ -154,6 +168,7 @@ export function createFollowupRunner(params: {
         if (entry) {
           sessionStore[sessionKey] = {
             ...entry,
+            modelProvider: fallbackProvider ?? entry.modelProvider,
             model: modelUsed ?? entry.model,
             contextTokens: contextTokensUsed ?? entry.contextTokens,
           };

src/auto-reply/status.ts

@@ -133,6 +133,7 @@ export function buildStatusMessage(args: StatusArgs): string {
     defaultProvider: DEFAULT_PROVIDER,
     defaultModel: DEFAULT_MODEL,
   });
+  const provider = entry?.modelProvider ?? resolved.provider ?? DEFAULT_PROVIDER;
   let model = entry?.model ?? resolved.model ?? DEFAULT_MODEL;
   let contextTokens =
     entry?.contextTokens ??
@@ -204,7 +205,7 @@ export function buildStatusMessage(args: StatusArgs): string {
 
   const optionsLine = `Options: thinking=${thinkLevel} | verbose=${verboseLevel} | elevated=${elevatedLevel} (set with /think <level>, /verbose on|off, /elevated on|off, /model <id>)`;
 
-  const modelLabel = model ? `${resolved.provider}/${model}` : "unknown";
+  const modelLabel = model ? `${provider}/${model}` : "unknown";
 
   const agentLine = `Agent: embedded pi • ${modelLabel}`;
 

src/cli/models-cli.ts

@@ -0,0 +1,198 @@
+import type { Command } from "commander";
+
+import {
+  modelsAliasesAddCommand,
+  modelsAliasesListCommand,
+  modelsAliasesRemoveCommand,
+  modelsFallbacksAddCommand,
+  modelsFallbacksClearCommand,
+  modelsFallbacksListCommand,
+  modelsFallbacksRemoveCommand,
+  modelsListCommand,
+  modelsScanCommand,
+  modelsSetCommand,
+  modelsStatusCommand,
+} from "../commands/models.js";
+import { defaultRuntime } from "../runtime.js";
+
+export function registerModelsCli(program: Command) {
+  const models = program
+    .command("models")
+    .description("Model discovery, scanning, and configuration");
+
+  models
+    .command("list")
+    .description("List models (configured by default)")
+    .option("--all", "Show full model catalog", false)
+    .option("--local", "Filter to local models", false)
+    .option("--provider <name>", "Filter by provider")
+    .option("--json", "Output JSON", false)
+    .option("--plain", "Plain line output", false)
+    .action(async (opts) => {
+      try {
+        await modelsListCommand(opts, defaultRuntime);
+      } catch (err) {
+        defaultRuntime.error(String(err));
+        defaultRuntime.exit(1);
+      }
+    });
+
+  models
+    .command("status")
+    .description("Show configured model state")
+    .option("--json", "Output JSON", false)
+    .option("--plain", "Plain output", false)
+    .action(async (opts) => {
+      try {
+        await modelsStatusCommand(opts, defaultRuntime);
+      } catch (err) {
+        defaultRuntime.error(String(err));
+        defaultRuntime.exit(1);
+      }
+    });
+
+  models
+    .command("set")
+    .description("Set the default model")
+    .argument("<model>", "Model id or alias")
+    .action(async (model: string) => {
+      try {
+        await modelsSetCommand(model, defaultRuntime);
+      } catch (err) {
+        defaultRuntime.error(String(err));
+        defaultRuntime.exit(1);
+      }
+    });
+
+  const aliases = models
+    .command("aliases")
+    .description("Manage model aliases");
+
+  aliases
+    .command("list")
+    .description("List model aliases")
+    .option("--json", "Output JSON", false)
+    .option("--plain", "Plain output", false)
+    .action(async (opts) => {
+      try {
+        await modelsAliasesListCommand(opts, defaultRuntime);
+      } catch (err) {
+        defaultRuntime.error(String(err));
+        defaultRuntime.exit(1);
+      }
+    });
+
+  aliases
+    .command("add")
+    .description("Add or update a model alias")
+    .argument("<alias>", "Alias name")
+    .argument("<model>", "Model id or alias")
+    .action(async (alias: string, model: string) => {
+      try {
+        await modelsAliasesAddCommand(alias, model, defaultRuntime);
+      } catch (err) {
+        defaultRuntime.error(String(err));
+        defaultRuntime.exit(1);
+      }
+    });
+
+  aliases
+    .command("remove")
+    .description("Remove a model alias")
+    .argument("<alias>", "Alias name")
+    .action(async (alias: string) => {
+      try {
+        await modelsAliasesRemoveCommand(alias, defaultRuntime);
+      } catch (err) {
+        defaultRuntime.error(String(err));
+        defaultRuntime.exit(1);
+      }
+    });
+
+  const fallbacks = models
+    .command("fallbacks")
+    .description("Manage model fallback list");
+
+  fallbacks
+    .command("list")
+    .description("List fallback models")
+    .option("--json", "Output JSON", false)
+    .option("--plain", "Plain output", false)
+    .action(async (opts) => {
+      try {
+        await modelsFallbacksListCommand(opts, defaultRuntime);
+      } catch (err) {
+        defaultRuntime.error(String(err));
+        defaultRuntime.exit(1);
+      }
+    });
+
+  fallbacks
+    .command("add")
+    .description("Add a fallback model")
+    .argument("<model>", "Model id or alias")
+    .action(async (model: string) => {
+      try {
+        await modelsFallbacksAddCommand(model, defaultRuntime);
+      } catch (err) {
+        defaultRuntime.error(String(err));
+        defaultRuntime.exit(1);
+      }
+    });
+
+  fallbacks
+    .command("remove")
+    .description("Remove a fallback model")
+    .argument("<model>", "Model id or alias")
+    .action(async (model: string) => {
+      try {
+        await modelsFallbacksRemoveCommand(model, defaultRuntime);
+      } catch (err) {
+        defaultRuntime.error(String(err));
+        defaultRuntime.exit(1);
+      }
+    });
+
+  fallbacks
+    .command("clear")
+    .description("Clear all fallback models")
+    .action(async () => {
+      try {
+        await modelsFallbacksClearCommand(defaultRuntime);
+      } catch (err) {
+        defaultRuntime.error(String(err));
+        defaultRuntime.exit(1);
+      }
+    });
+
+  models
+    .command("scan")
+    .description("Scan OpenRouter free models for tools + images")
+    .option("--min-params <b>", "Minimum parameter size (billions)")
+    .option("--max-age-days <days>", "Skip models older than N days")
+    .option("--provider <name>", "Filter by provider prefix")
+    .option("--max-candidates <n>", "Max fallback candidates", "6")
+    .option("--timeout <ms>", "Per-probe timeout in ms")
+    .option("--concurrency <n>", "Probe concurrency")
+    .option("--yes", "Accept defaults without prompting", false)
+    .option("--no-input", "Disable prompts (use defaults)")
+    .option("--set-default", "Set agent.model to the first selection", false)
+    .option("--json", "Output JSON", false)
+    .action(async (opts) => {
+      try {
+        await modelsScanCommand(opts, defaultRuntime);
+      } catch (err) {
+        defaultRuntime.error(String(err));
+        defaultRuntime.exit(1);
+      }
+    });
+
+  models.action(async () => {
+    try {
+      await modelsStatusCommand({}, defaultRuntime);
+    } catch (err) {
+      defaultRuntime.error(String(err));
+      defaultRuntime.exit(1);
+    }
+  });
+}

src/cli/program.ts

@@ -22,6 +22,7 @@ import { createDefaultDeps } from "./deps.js";
 import { registerDnsCli } from "./dns-cli.js";
 import { registerGatewayCli } from "./gateway-cli.js";
 import { registerHooksCli } from "./hooks-cli.js";
+import { registerModelsCli } from "./models-cli.js";
 import { registerNodesCli } from "./nodes-cli.js";
 import { forceFreePort } from "./ports.js";
 import { registerTuiCli } from "./tui-cli.js";
@@ -399,6 +400,7 @@ Examples:
 
   registerCanvasCli(program);
   registerGatewayCli(program);
+  registerModelsCli(program);
   registerNodesCli(program);
   registerTuiCli(program);
   registerCronCli(program);

src/commands/agent.ts

@@ -12,6 +12,7 @@ import {
   resolveConfiguredModelRef,
   resolveThinkingDefault,
 } from "../agents/model-selection.js";
+import { runWithModelFallback } from "../agents/model-fallback.js";
 import { runEmbeddedPiAgent } from "../agents/pi-embedded.js";
 import { buildWorkspaceSkillSnapshot } from "../agents/skills.js";
 import {
@@ -364,6 +365,8 @@ export async function agentCommand(
   });
 
   let result: Awaited<ReturnType<typeof runEmbeddedPiAgent>>;
+  let fallbackProvider = provider;
+  let fallbackModel = model;
   try {
     const surface =
       opts.surface?.trim().toLowerCase() ||
@@ -372,7 +375,12 @@ export async function agentCommand(
         if (!raw) return undefined;
         return raw === "imsg" ? "imessage" : raw;
       })();
-    result = await runEmbeddedPiAgent({
+    const fallbackResult = await runWithModelFallback({
+      cfg,
+      provider,
+      model,
+      run: (providerOverride, modelOverride) =>
+        runEmbeddedPiAgent({
           sessionId,
           sessionKey,
           surface,
@@ -381,8 +389,8 @@ export async function agentCommand(
           config: cfg,
           skillsSnapshot,
           prompt: body,
-      provider,
+          provider: providerOverride,
-      model,
+          model: modelOverride,
           thinkLevel: resolvedThinkLevel,
           verboseLevel: resolvedVerboseLevel,
           timeoutMs,
@@ -397,7 +405,11 @@ export async function agentCommand(
               data: evt.data,
             });
           },
+        }),
     });
+    result = fallbackResult.result;
+    fallbackProvider = fallbackResult.provider;
+    fallbackModel = fallbackResult.model;
     emitAgentEvent({
       runId,
       stream: "job",
@@ -431,7 +443,10 @@ export async function agentCommand(
   // Update token+model fields in the session store.
   if (sessionStore && sessionKey) {
     const usage = result.meta.agentMeta?.usage;
-    const modelUsed = result.meta.agentMeta?.model ?? model;
+    const modelUsed =
+      result.meta.agentMeta?.model ?? fallbackModel ?? model;
+    const providerUsed =
+      result.meta.agentMeta?.provider ?? fallbackProvider ?? provider;
     const contextTokens =
       agentCfg?.contextTokens ??
       lookupContextTokens(modelUsed) ??
@@ -445,6 +460,7 @@ export async function agentCommand(
       ...entry,
       sessionId,
       updatedAt: Date.now(),
+      modelProvider: providerUsed,
       model: modelUsed,
       contextTokens,
     };

src/commands/models.ts

@@ -0,0 +1,14 @@
+export { modelsListCommand, modelsStatusCommand } from "./models/list.js";
+export {
+  modelsAliasesAddCommand,
+  modelsAliasesListCommand,
+  modelsAliasesRemoveCommand,
+} from "./models/aliases.js";
+export {
+  modelsFallbacksAddCommand,
+  modelsFallbacksClearCommand,
+  modelsFallbacksListCommand,
+  modelsFallbacksRemoveCommand,
+} from "./models/fallbacks.js";
+export { modelsScanCommand } from "./models/scan.js";
+export { modelsSetCommand } from "./models/set.js";

src/commands/models/aliases.ts

@@ -0,0 +1,89 @@
+import {
+  CONFIG_PATH_CLAWDBOT,
+  loadConfig,
+} from "../../config/config.js";
+import type { RuntimeEnv } from "../../runtime.js";
+import {
+  ensureFlagCompatibility,
+  normalizeAlias,
+  resolveModelTarget,
+  updateConfig,
+} from "./shared.js";
+
+export async function modelsAliasesListCommand(
+  opts: { json?: boolean; plain?: boolean },
+  runtime: RuntimeEnv,
+) {
+  ensureFlagCompatibility(opts);
+  const cfg = loadConfig();
+  const aliases = cfg.agent?.modelAliases ?? {};
+
+  if (opts.json) {
+    runtime.log(JSON.stringify({ aliases }, null, 2));
+    return;
+  }
+  if (opts.plain) {
+    for (const [alias, target] of Object.entries(aliases)) {
+      runtime.log(`${alias} ${target}`);
+    }
+    return;
+  }
+
+  runtime.log(`Aliases (${Object.keys(aliases).length}):`);
+  if (Object.keys(aliases).length === 0) {
+    runtime.log("- none");
+    return;
+  }
+  for (const [alias, target] of Object.entries(aliases)) {
+    runtime.log(`- ${alias} -> ${target}`);
+  }
+}
+
+export async function modelsAliasesAddCommand(
+  aliasRaw: string,
+  modelRaw: string,
+  runtime: RuntimeEnv,
+) {
+  const alias = normalizeAlias(aliasRaw);
+  const updated = await updateConfig((cfg) => {
+    const resolved = resolveModelTarget({ raw: modelRaw, cfg });
+    const nextAliases = { ...(cfg.agent?.modelAliases ?? {}) };
+    nextAliases[alias] = `${resolved.provider}/${resolved.model}`;
+    return {
+      ...cfg,
+      agent: {
+        ...cfg.agent,
+        modelAliases: nextAliases,
+      },
+    };
+  });
+
+  runtime.log(`Updated ${CONFIG_PATH_CLAWDBOT}`);
+  runtime.log(`Alias ${alias} -> ${updated.agent?.modelAliases?.[alias]}`);
+}
+
+export async function modelsAliasesRemoveCommand(
+  aliasRaw: string,
+  runtime: RuntimeEnv,
+) {
+  const alias = normalizeAlias(aliasRaw);
+  const updated = await updateConfig((cfg) => {
+    const nextAliases = { ...(cfg.agent?.modelAliases ?? {}) };
+    if (!nextAliases[alias]) {
+      throw new Error(`Alias not found: ${alias}`);
+    }
+    delete nextAliases[alias];
+    return {
+      ...cfg,
+      agent: {
+        ...cfg.agent,
+        modelAliases: nextAliases,
+      },
+    };
+  });
+
+  runtime.log(`Updated ${CONFIG_PATH_CLAWDBOT}`);
+  if (!updated.agent?.modelAliases || Object.keys(updated.agent.modelAliases).length === 0) {
+    runtime.log("No aliases configured.");
+  }
+}

src/commands/models/fallbacks.ts

@@ -0,0 +1,134 @@
+import {
+  CONFIG_PATH_CLAWDBOT,
+  loadConfig,
+} from "../../config/config.js";
+import type { RuntimeEnv } from "../../runtime.js";
+import {
+  buildModelAliasIndex,
+  resolveModelRefFromString,
+} from "../../agents/model-selection.js";
+import {
+  DEFAULT_PROVIDER,
+  ensureFlagCompatibility,
+  modelKey,
+  resolveModelTarget,
+  updateConfig,
+} from "./shared.js";
+
+export async function modelsFallbacksListCommand(
+  opts: { json?: boolean; plain?: boolean },
+  runtime: RuntimeEnv,
+) {
+  ensureFlagCompatibility(opts);
+  const cfg = loadConfig();
+  const fallbacks = cfg.agent?.modelFallbacks ?? [];
+
+  if (opts.json) {
+    runtime.log(JSON.stringify({ fallbacks }, null, 2));
+    return;
+  }
+  if (opts.plain) {
+    for (const entry of fallbacks) runtime.log(entry);
+    return;
+  }
+
+  runtime.log(`Fallbacks (${fallbacks.length}):`);
+  if (fallbacks.length === 0) {
+    runtime.log("- none");
+    return;
+  }
+  for (const entry of fallbacks) runtime.log(`- ${entry}`);
+}
+
+export async function modelsFallbacksAddCommand(
+  modelRaw: string,
+  runtime: RuntimeEnv,
+) {
+  const updated = await updateConfig((cfg) => {
+    const resolved = resolveModelTarget({ raw: modelRaw, cfg });
+    const targetKey = modelKey(resolved.provider, resolved.model);
+    const aliasIndex = buildModelAliasIndex({
+      cfg,
+      defaultProvider: DEFAULT_PROVIDER,
+    });
+    const existing = cfg.agent?.modelFallbacks ?? [];
+    const existingKeys = existing
+      .map((entry) =>
+        resolveModelRefFromString({
+          raw: String(entry ?? ""),
+          defaultProvider: DEFAULT_PROVIDER,
+          aliasIndex,
+        }),
+      )
+      .filter(Boolean)
+      .map((entry) => modelKey(entry!.ref.provider, entry!.ref.model));
+
+    if (existingKeys.includes(targetKey)) return cfg;
+
+    return {
+      ...cfg,
+      agent: {
+        ...cfg.agent,
+        modelFallbacks: [...existing, targetKey],
+      },
+    };
+  });
+
+  runtime.log(`Updated ${CONFIG_PATH_CLAWDBOT}`);
+  runtime.log(`Fallbacks: ${(updated.agent?.modelFallbacks ?? []).join(", ")}`);
+}
+
+export async function modelsFallbacksRemoveCommand(
+  modelRaw: string,
+  runtime: RuntimeEnv,
+) {
+  const updated = await updateConfig((cfg) => {
+    const resolved = resolveModelTarget({ raw: modelRaw, cfg });
+    const targetKey = modelKey(resolved.provider, resolved.model);
+    const aliasIndex = buildModelAliasIndex({
+      cfg,
+      defaultProvider: DEFAULT_PROVIDER,
+    });
+    const existing = cfg.agent?.modelFallbacks ?? [];
+    const filtered = existing.filter((entry) => {
+      const resolvedEntry = resolveModelRefFromString({
+        raw: String(entry ?? ""),
+        defaultProvider: DEFAULT_PROVIDER,
+        aliasIndex,
+      });
+      if (!resolvedEntry) return true;
+      return (
+        modelKey(resolvedEntry.ref.provider, resolvedEntry.ref.model) !==
+        targetKey
+      );
+    });
+
+    if (filtered.length === existing.length) {
+      throw new Error(`Fallback not found: ${targetKey}`);
+    }
+
+    return {
+      ...cfg,
+      agent: {
+        ...cfg.agent,
+        modelFallbacks: filtered,
+      },
+    };
+  });
+
+  runtime.log(`Updated ${CONFIG_PATH_CLAWDBOT}`);
+  runtime.log(`Fallbacks: ${(updated.agent?.modelFallbacks ?? []).join(", ")}`);
+}
+
+export async function modelsFallbacksClearCommand(runtime: RuntimeEnv) {
+  await updateConfig((cfg) => ({
+    ...cfg,
+    agent: {
+      ...cfg.agent,
+      modelFallbacks: [],
+    },
+  }));
+
+  runtime.log(`Updated ${CONFIG_PATH_CLAWDBOT}`);
+  runtime.log("Fallback list cleared.");
+}

src/commands/models/list.ts

@@ -0,0 +1,419 @@
+import chalk from "chalk";
+import {
+  discoverAuthStorage,
+  discoverModels,
+} from "@mariozechner/pi-coding-agent";
+import { getEnvApiKey, type Api, type Model } from "@mariozechner/pi-ai";
+
+import { resolveClawdbotAgentDir } from "../../agents/agent-paths.js";
+import { ensureClawdbotModelsJson } from "../../agents/models-config.js";
+import {
+  buildModelAliasIndex,
+  parseModelRef,
+  resolveModelRefFromString,
+  resolveConfiguredModelRef,
+} from "../../agents/model-selection.js";
+import {
+  CONFIG_PATH_CLAWDBOT,
+  loadConfig,
+  type ClawdbotConfig,
+} from "../../config/config.js";
+import { info } from "../../globals.js";
+import type { RuntimeEnv } from "../../runtime.js";
+import {
+  DEFAULT_MODEL,
+  DEFAULT_PROVIDER,
+  ensureFlagCompatibility,
+  formatTokenK,
+  modelKey,
+} from "./shared.js";
+
+const MODEL_PAD = 42;
+const INPUT_PAD = 10;
+const CTX_PAD = 8;
+const LOCAL_PAD = 5;
+const AUTH_PAD = 5;
+
+const isRich = (opts?: { json?: boolean; plain?: boolean }) =>
+  Boolean(process.stdout.isTTY && chalk.level > 0 && !opts?.json && !opts?.plain);
+
+const pad = (value: string, size: number) => value.padEnd(size);
+
+const truncate = (value: string, max: number) => {
+  if (value.length <= max) return value;
+  if (max <= 3) return value.slice(0, max);
+  return `${value.slice(0, max - 3)}...`;
+};
+
+type ConfiguredEntry = {
+  key: string;
+  ref: { provider: string; model: string };
+  tags: Set<string>;
+  aliases: string[];
+};
+
+type ModelRow = {
+  key: string;
+  name: string;
+  input: string;
+  contextWindow: number | null;
+  local: boolean | null;
+  available: boolean | null;
+  tags: string[];
+  missing: boolean;
+};
+
+const isLocalBaseUrl = (baseUrl: string) => {
+  try {
+    const url = new URL(baseUrl);
+    const host = url.hostname.toLowerCase();
+    return (
+      host === "localhost" ||
+      host === "127.0.0.1" ||
+      host === "0.0.0.0" ||
+      host === "::1" ||
+      host.endsWith(".local")
+    );
+  } catch {
+    return false;
+  }
+};
+
+const resolveConfiguredEntries = (cfg: ClawdbotConfig) => {
+  const resolvedDefault = resolveConfiguredModelRef({
+    cfg,
+    defaultProvider: DEFAULT_PROVIDER,
+    defaultModel: DEFAULT_MODEL,
+  });
+  const aliasIndex = buildModelAliasIndex({
+    cfg,
+    defaultProvider: DEFAULT_PROVIDER,
+  });
+  const order: string[] = [];
+  const tagsByKey = new Map<string, Set<string>>();
+  const aliasesByKey = new Map<string, string[]>();
+
+  for (const [key, aliases] of aliasIndex.byKey.entries()) {
+    aliasesByKey.set(key, aliases);
+  }
+
+  const addEntry = (ref: { provider: string; model: string }, tag: string) => {
+    const key = modelKey(ref.provider, ref.model);
+    if (!tagsByKey.has(key)) {
+      tagsByKey.set(key, new Set());
+      order.push(key);
+    }
+    tagsByKey.get(key)?.add(tag);
+  };
+
+  addEntry(resolvedDefault, "default");
+
+  (cfg.agent?.modelFallbacks ?? []).forEach((raw, idx) => {
+    const resolved = resolveModelRefFromString({
+      raw: String(raw ?? ""),
+      defaultProvider: DEFAULT_PROVIDER,
+      aliasIndex,
+    });
+    if (!resolved) return;
+    addEntry(resolved.ref, `fallback#${idx + 1}`);
+  });
+
+  (cfg.agent?.allowedModels ?? []).forEach((raw) => {
+    const parsed = parseModelRef(String(raw ?? ""), DEFAULT_PROVIDER);
+    if (!parsed) return;
+    addEntry(parsed, "allowed");
+  });
+
+  for (const targetRaw of Object.values(cfg.agent?.modelAliases ?? {})) {
+    const resolved = resolveModelRefFromString({
+      raw: String(targetRaw ?? ""),
+      defaultProvider: DEFAULT_PROVIDER,
+      aliasIndex,
+    });
+    if (!resolved) continue;
+    addEntry(resolved.ref, "alias");
+  }
+
+  const entries: ConfiguredEntry[] = order.map((key) => {
+    const slash = key.indexOf("/");
+    const provider = slash === -1 ? key : key.slice(0, slash);
+    const model = slash === -1 ? "" : key.slice(slash + 1);
+    return {
+      key,
+      ref: { provider, model },
+      tags: tagsByKey.get(key) ?? new Set(),
+      aliases: aliasesByKey.get(key) ?? [],
+    } satisfies ConfiguredEntry;
+  });
+
+  return { entries };
+};
+
+async function loadModelRegistry(cfg: ClawdbotConfig) {
+  await ensureClawdbotModelsJson(cfg);
+  const agentDir = resolveClawdbotAgentDir();
+  const authStorage = discoverAuthStorage(agentDir);
+  const registry = discoverModels(authStorage, agentDir);
+  const models = registry.getAll() as Model<Api>[];
+  const availableModels = registry.getAvailable() as Model<Api>[];
+  const availableKeys = new Set(
+    availableModels.map((model) => modelKey(model.provider, model.id)),
+  );
+  return { registry, models, availableKeys };
+}
+
+function toModelRow(params: {
+  model?: Model<Api>;
+  key: string;
+  tags: string[];
+  aliases?: string[];
+  availableKeys?: Set<string>;
+}): ModelRow {
+  const { model, key, tags, aliases = [], availableKeys } = params;
+  if (!model) {
+    return {
+      key,
+      name: key,
+      input: "-",
+      contextWindow: null,
+      local: null,
+      available: null,
+      tags: [...tags, "missing"],
+      missing: true,
+    };
+  }
+
+  const input = model.input.join("+") || "text";
+  const local = isLocalBaseUrl(model.baseUrl);
+  const envKey = getEnvApiKey(model.provider);
+  const available =
+    availableKeys?.has(modelKey(model.provider, model.id)) || Boolean(envKey);
+  const aliasTags = aliases.length > 0 ? [`alias:${aliases.join(",")}`] : [];
+  const mergedTags = new Set(tags);
+  if (aliasTags.length > 0) {
+    for (const tag of mergedTags) {
+      if (tag === "alias" || tag.startsWith("alias:")) mergedTags.delete(tag);
+    }
+    for (const tag of aliasTags) mergedTags.add(tag);
+  }
+
+  return {
+    key,
+    name: model.name || model.id,
+    input,
+    contextWindow: model.contextWindow ?? null,
+    local,
+    available,
+    tags: Array.from(mergedTags),
+    missing: false,
+  };
+}
+
+function printModelTable(
+  rows: ModelRow[],
+  runtime: RuntimeEnv,
+  opts: { json?: boolean; plain?: boolean } = {},
+) {
+  if (opts.json) {
+    runtime.log(
+      JSON.stringify(
+        {
+          count: rows.length,
+          models: rows,
+        },
+        null,
+        2,
+      ),
+    );
+    return;
+  }
+
+  if (opts.plain) {
+    for (const row of rows) runtime.log(row.key);
+    return;
+  }
+
+  const rich = isRich(opts);
+  const header = [
+    pad("Model", MODEL_PAD),
+    pad("Input", INPUT_PAD),
+    pad("Ctx", CTX_PAD),
+    pad("Local", LOCAL_PAD),
+    pad("Auth", AUTH_PAD),
+    "Tags",
+  ].join(" ");
+  runtime.log(rich ? chalk.bold(header) : header);
+
+  for (const row of rows) {
+    const keyLabel = pad(truncate(row.key, MODEL_PAD), MODEL_PAD);
+    const inputLabel = pad(row.input || "-", INPUT_PAD);
+    const ctxLabel = pad(formatTokenK(row.contextWindow), CTX_PAD);
+    const localLabel = pad(
+      row.local === null ? "-" : row.local ? "yes" : "no",
+      LOCAL_PAD,
+    );
+    const authLabel = pad(
+      row.available === null ? "-" : row.available ? "yes" : "no",
+      AUTH_PAD,
+    );
+    const tagsLabel = row.tags.length > 0 ? row.tags.join(",") : "";
+
+    const line = [
+      rich ? chalk.cyan(keyLabel) : keyLabel,
+      inputLabel,
+      ctxLabel,
+      localLabel,
+      authLabel,
+      rich ? chalk.gray(tagsLabel) : tagsLabel,
+    ].join(" ");
+    runtime.log(line);
+  }
+}
+
+export async function modelsListCommand(
+  opts: {
+    all?: boolean;
+    local?: boolean;
+    provider?: string;
+    json?: boolean;
+    plain?: boolean;
+  },
+  runtime: RuntimeEnv,
+) {
+  ensureFlagCompatibility(opts);
+  const cfg = loadConfig();
+  const providerFilter = opts.provider?.trim().toLowerCase();
+
+  let models: Model<Api>[] = [];
+  let availableKeys: Set<string> | undefined;
+  try {
+    const loaded = await loadModelRegistry(cfg);
+    models = loaded.models;
+    availableKeys = loaded.availableKeys;
+  } catch (err) {
+    runtime.error(`Model registry unavailable: ${String(err)}`);
+  }
+
+  const modelByKey = new Map(
+    models.map((model) => [modelKey(model.provider, model.id), model]),
+  );
+
+  const { entries } = resolveConfiguredEntries(cfg);
+  const configuredByKey = new Map(entries.map((entry) => [entry.key, entry]));
+
+  const rows: ModelRow[] = [];
+
+  if (opts.all) {
+    const sorted = [...models].sort((a, b) => {
+      const p = a.provider.localeCompare(b.provider);
+      if (p !== 0) return p;
+      return a.id.localeCompare(b.id);
+    });
+
+    for (const model of sorted) {
+      if (providerFilter && model.provider.toLowerCase() !== providerFilter) {
+        continue;
+      }
+      if (opts.local && !isLocalBaseUrl(model.baseUrl)) continue;
+      const key = modelKey(model.provider, model.id);
+      const configured = configuredByKey.get(key);
+      rows.push(
+        toModelRow({
+          model,
+          key,
+          tags: configured ? Array.from(configured.tags) : [],
+          aliases: configured?.aliases ?? [],
+          availableKeys,
+        }),
+      );
+    }
+  } else {
+    for (const entry of entries) {
+      if (
+        providerFilter &&
+        entry.ref.provider.toLowerCase() !== providerFilter
+      ) {
+        continue;
+      }
+      const model = modelByKey.get(entry.key);
+      if (opts.local && model && !isLocalBaseUrl(model.baseUrl)) continue;
+      if (opts.local && !model) continue;
+      rows.push(
+        toModelRow({
+          model,
+          key: entry.key,
+          tags: Array.from(entry.tags),
+          aliases: entry.aliases,
+          availableKeys,
+        }),
+      );
+    }
+  }
+
+  if (rows.length === 0) {
+    runtime.log("No models found.");
+    return;
+  }
+
+  printModelTable(rows, runtime, opts);
+}
+
+export async function modelsStatusCommand(
+  opts: { json?: boolean; plain?: boolean },
+  runtime: RuntimeEnv,
+) {
+  ensureFlagCompatibility(opts);
+  const cfg = loadConfig();
+  const resolved = resolveConfiguredModelRef({
+    cfg,
+    defaultProvider: DEFAULT_PROVIDER,
+    defaultModel: DEFAULT_MODEL,
+  });
+
+  const rawModel = cfg.agent?.model?.trim() ?? "";
+  const defaultLabel = rawModel || `${resolved.provider}/${resolved.model}`;
+  const fallbacks = cfg.agent?.modelFallbacks ?? [];
+  const aliases = cfg.agent?.modelAliases ?? {};
+  const allowed = cfg.agent?.allowedModels ?? [];
+
+  if (opts.json) {
+    runtime.log(
+      JSON.stringify(
+        {
+          configPath: CONFIG_PATH_CLAWDBOT,
+          defaultModel: defaultLabel,
+          resolvedDefault: `${resolved.provider}/${resolved.model}`,
+          fallbacks,
+          aliases,
+          allowed,
+        },
+        null,
+        2,
+      ),
+    );
+    return;
+  }
+
+  if (opts.plain) {
+    runtime.log(defaultLabel);
+    return;
+  }
+
+  runtime.log(info(`Config: ${CONFIG_PATH_CLAWDBOT}`));
+  runtime.log(`Default: ${defaultLabel}`);
+  runtime.log(
+    `Fallbacks (${fallbacks.length || 0}): ${fallbacks.join(", ") || "-"}`,
+  );
+  runtime.log(
+    `Aliases (${Object.keys(aliases).length || 0}): ${
+      Object.keys(aliases).length
+        ? Object.entries(aliases)
+            .map(([alias, target]) => `${alias} -> ${target}`)
+            .join(", ")
+        : "-"
+    }`,
+  );
+  runtime.log(
+    `Allowed (${allowed.length || 0}): ${allowed.length ? allowed.join(", ") : "all"}`,
+  );
+}

src/commands/models/scan.ts

@@ -0,0 +1,267 @@
+import { cancel, isCancel, multiselect } from "@clack/prompts";
+import { discoverAuthStorage } from "@mariozechner/pi-coding-agent";
+
+import { resolveClawdbotAgentDir } from "../../agents/agent-paths.js";
+import {
+  scanOpenRouterModels,
+  type ModelScanResult,
+} from "../../agents/model-scan.js";
+import { warn } from "../../globals.js";
+import type { RuntimeEnv } from "../../runtime.js";
+import {
+  buildAllowlistSet,
+  formatMs,
+  formatTokenK,
+  updateConfig,
+} from "./shared.js";
+import { CONFIG_PATH_CLAWDBOT } from "../../config/config.js";
+
+const MODEL_PAD = 42;
+const CTX_PAD = 8;
+
+const pad = (value: string, size: number) => value.padEnd(size);
+
+const truncate = (value: string, max: number) => {
+  if (value.length <= max) return value;
+  if (max <= 3) return value.slice(0, max);
+  return `${value.slice(0, max - 3)}...`;
+};
+
+
+function sortScanResults(results: ModelScanResult[]): ModelScanResult[] {
+  return results.slice().sort((a, b) => {
+    const aImage = a.image.ok ? 1 : 0;
+    const bImage = b.image.ok ? 1 : 0;
+    if (aImage !== bImage) return bImage - aImage;
+
+    const aToolLatency = a.tool.latencyMs ?? Number.POSITIVE_INFINITY;
+    const bToolLatency = b.tool.latencyMs ?? Number.POSITIVE_INFINITY;
+    if (aToolLatency !== bToolLatency) return aToolLatency - bToolLatency;
+
+    const aCtx = a.contextLength ?? 0;
+    const bCtx = b.contextLength ?? 0;
+    if (aCtx !== bCtx) return bCtx - aCtx;
+
+    const aParams = a.inferredParamB ?? 0;
+    const bParams = b.inferredParamB ?? 0;
+    if (aParams !== bParams) return bParams - aParams;
+
+    return a.modelRef.localeCompare(b.modelRef);
+  });
+}
+
+function buildScanHint(result: ModelScanResult): string {
+  const toolLabel = result.tool.ok
+    ? `tool ${formatMs(result.tool.latencyMs)}`
+    : "tool fail";
+  const imageLabel = result.image.skipped
+    ? "img skip"
+    : result.image.ok
+      ? `img ${formatMs(result.image.latencyMs)}`
+      : "img fail";
+  const ctxLabel = result.contextLength
+    ? `ctx ${formatTokenK(result.contextLength)}`
+    : "ctx ?";
+  const paramLabel = result.inferredParamB ? `${result.inferredParamB}b` : null;
+  return [toolLabel, imageLabel, ctxLabel, paramLabel]
+    .filter(Boolean)
+    .join(" | ");
+}
+
+function printScanSummary(results: ModelScanResult[], runtime: RuntimeEnv) {
+  const toolOk = results.filter((r) => r.tool.ok);
+  const imageOk = results.filter((r) => r.image.ok);
+  const toolImageOk = results.filter((r) => r.tool.ok && r.image.ok);
+  runtime.log(
+    `Scan results: tested ${results.length}, tool ok ${toolOk.length}, image ok ${imageOk.length}, tool+image ok ${toolImageOk.length}`,
+  );
+}
+
+function printScanTable(results: ModelScanResult[], runtime: RuntimeEnv) {
+  const header = [
+    pad("Model", MODEL_PAD),
+    pad("Tool", 10),
+    pad("Image", 10),
+    pad("Ctx", CTX_PAD),
+    pad("Params", 8),
+    "Notes",
+  ].join(" ");
+  runtime.log(header);
+
+  for (const entry of results) {
+    const modelLabel = pad(truncate(entry.modelRef, MODEL_PAD), MODEL_PAD);
+    const toolLabel = pad(
+      entry.tool.ok ? formatMs(entry.tool.latencyMs) : "fail",
+      10,
+    );
+    const imageLabel = pad(
+      entry.image.ok
+        ? formatMs(entry.image.latencyMs)
+        : entry.image.skipped
+          ? "skip"
+          : "fail",
+      10,
+    );
+    const ctxLabel = pad(formatTokenK(entry.contextLength), CTX_PAD);
+    const paramsLabel = pad(
+      entry.inferredParamB ? `${entry.inferredParamB}b` : "-",
+      8,
+    );
+    const notes = entry.modality ? `modality:${entry.modality}` : "";
+
+    runtime.log(
+      [modelLabel, toolLabel, imageLabel, ctxLabel, paramsLabel, notes].join(
+        " ",
+      ),
+    );
+  }
+}
+
+export async function modelsScanCommand(
+  opts: {
+    minParams?: string;
+    maxAgeDays?: string;
+    provider?: string;
+    maxCandidates?: string;
+    timeout?: string;
+    concurrency?: string;
+    yes?: boolean;
+    input?: boolean;
+    setDefault?: boolean;
+    json?: boolean;
+  },
+  runtime: RuntimeEnv,
+) {
+  const minParams = opts.minParams ? Number(opts.minParams) : undefined;
+  if (minParams !== undefined && (!Number.isFinite(minParams) || minParams < 0)) {
+    throw new Error("--min-params must be >= 0");
+  }
+  const maxAgeDays = opts.maxAgeDays ? Number(opts.maxAgeDays) : undefined;
+  if (maxAgeDays !== undefined && (!Number.isFinite(maxAgeDays) || maxAgeDays < 0)) {
+    throw new Error("--max-age-days must be >= 0");
+  }
+  const maxCandidates = opts.maxCandidates
+    ? Number(opts.maxCandidates)
+    : 6;
+  if (!Number.isFinite(maxCandidates) || maxCandidates <= 0) {
+    throw new Error("--max-candidates must be > 0");
+  }
+  const timeout = opts.timeout ? Number(opts.timeout) : undefined;
+  if (timeout !== undefined && (!Number.isFinite(timeout) || timeout <= 0)) {
+    throw new Error("--timeout must be > 0");
+  }
+  const concurrency = opts.concurrency ? Number(opts.concurrency) : undefined;
+  if (concurrency !== undefined && (!Number.isFinite(concurrency) || concurrency <= 0)) {
+    throw new Error("--concurrency must be > 0");
+  }
+
+  const authStorage = discoverAuthStorage(resolveClawdbotAgentDir());
+  const storedKey = await authStorage.getApiKey("openrouter");
+  const results = await scanOpenRouterModels({
+    apiKey: storedKey ?? undefined,
+    minParamB: minParams,
+    maxAgeDays,
+    providerFilter: opts.provider,
+    timeoutMs: timeout,
+    concurrency,
+  });
+
+  const toolOk = results.filter((entry) => entry.tool.ok);
+  if (toolOk.length === 0) {
+    throw new Error("No tool-capable OpenRouter free models found.");
+  }
+
+  const sorted = sortScanResults(toolOk);
+  const imagePreferred = sorted.filter((entry) => entry.image.ok);
+  const preselectPool = imagePreferred.length > 0 ? imagePreferred : sorted;
+  const preselected = preselectPool
+    .slice(0, Math.floor(maxCandidates))
+    .map((entry) => entry.modelRef);
+
+  if (!opts.json) {
+    printScanSummary(results, runtime);
+    printScanTable(sorted, runtime);
+  }
+
+  const noInput = opts.input === false;
+  const canPrompt = process.stdin.isTTY && !opts.yes && !noInput && !opts.json;
+  let selected: string[] = preselected;
+
+  if (canPrompt) {
+    const selection = await multiselect({
+      message: "Select fallback models (ordered)",
+      options: sorted.map((entry) => ({
+        value: entry.modelRef,
+        label: entry.modelRef,
+        hint: buildScanHint(entry),
+      })),
+      initialValues: preselected,
+    });
+
+    if (isCancel(selection)) {
+      cancel("Model scan cancelled.");
+      runtime.exit(0);
+    }
+
+    selected = selection as string[];
+  } else if (!process.stdin.isTTY && !opts.yes && !noInput && !opts.json) {
+    throw new Error("Non-interactive scan: pass --yes to apply defaults.");
+  }
+
+  if (selected.length === 0) {
+    throw new Error("No models selected for fallbacks.");
+  }
+
+  const updated = await updateConfig((cfg) => {
+    const next = {
+      ...cfg,
+      agent: {
+        ...cfg.agent,
+        modelFallbacks: selected,
+        ...(opts.setDefault ? { model: selected[0] } : {}),
+      },
+    };
+    return next;
+  });
+
+  const allowlist = buildAllowlistSet(updated);
+  const allowlistMissing =
+    allowlist.size > 0
+      ? selected.filter((entry) => !allowlist.has(entry))
+      : [];
+
+  if (opts.json) {
+    runtime.log(
+      JSON.stringify(
+        {
+          selected,
+          setDefault: Boolean(opts.setDefault),
+          results,
+          warnings:
+            allowlistMissing.length > 0
+              ? [
+                  `Selected models not in agent.allowedModels: ${allowlistMissing.join(", ")}`,
+                ]
+              : [],
+        },
+        null,
+        2,
+      ),
+    );
+    return;
+  }
+
+  if (allowlistMissing.length > 0) {
+    runtime.log(
+      warn(
+        `Warning: ${allowlistMissing.length} selected models are not in agent.allowedModels and will be ignored by fallback: ${allowlistMissing.join(", ")}`,
+      ),
+    );
+  }
+
+  runtime.log(`Updated ${CONFIG_PATH_CLAWDBOT}`);
+  runtime.log(`Fallbacks: ${selected.join(", ")}`);
+  if (opts.setDefault) {
+    runtime.log(`Default model: ${selected[0]}`);
+  }
+}

src/commands/models/set.ts

@@ -0,0 +1,29 @@
+import { CONFIG_PATH_CLAWDBOT } from "../../config/config.js";
+import type { RuntimeEnv } from "../../runtime.js";
+import { buildAllowlistSet, modelKey, resolveModelTarget, updateConfig } from "./shared.js";
+
+export async function modelsSetCommand(
+  modelRaw: string,
+  runtime: RuntimeEnv,
+) {
+  const updated = await updateConfig((cfg) => {
+    const resolved = resolveModelTarget({ raw: modelRaw, cfg });
+    const allowlist = buildAllowlistSet(cfg);
+    if (allowlist.size > 0) {
+      const key = modelKey(resolved.provider, resolved.model);
+      if (!allowlist.has(key)) {
+        throw new Error(`Model ${key} is not in agent.allowedModels.`);
+      }
+    }
+    return {
+      ...cfg,
+      agent: {
+        ...cfg.agent,
+        model: `${resolved.provider}/${resolved.model}`,
+      },
+    };
+  });
+
+  runtime.log(`Updated ${CONFIG_PATH_CLAWDBOT}`);
+  runtime.log(`Default model: ${updated.agent?.model ?? modelRaw}`);
+}

src/commands/models/shared.ts

@@ -0,0 +1,95 @@
+import {
+  DEFAULT_MODEL,
+  DEFAULT_PROVIDER,
+} from "../../agents/defaults.js";
+import {
+  buildModelAliasIndex,
+  modelKey,
+  parseModelRef,
+  resolveModelRefFromString,
+} from "../../agents/model-selection.js";
+import {
+  readConfigFileSnapshot,
+  writeConfigFile,
+  type ClawdbotConfig,
+} from "../../config/config.js";
+
+export const ensureFlagCompatibility = (opts: {
+  json?: boolean;
+  plain?: boolean;
+}) => {
+  if (opts.json && opts.plain) {
+    throw new Error("Choose either --json or --plain, not both.");
+  }
+};
+
+export const formatTokenK = (value?: number | null) => {
+  if (!value || !Number.isFinite(value)) return "-";
+  if (value < 1024) return `${Math.round(value)}`;
+  return `${Math.round(value / 1024)}k`;
+};
+
+export const formatMs = (value?: number | null) => {
+  if (value === null || value === undefined) return "-";
+  if (!Number.isFinite(value)) return "-";
+  if (value < 1000) return `${Math.round(value)}ms`;
+  return `${Math.round(value / 100) / 10}s`;
+};
+
+export async function updateConfig(
+  mutator: (cfg: ClawdbotConfig) => ClawdbotConfig,
+): Promise<ClawdbotConfig> {
+  const snapshot = await readConfigFileSnapshot();
+  if (!snapshot.valid) {
+    const issues = snapshot.issues
+      .map((issue) => `- ${issue.path}: ${issue.message}`)
+      .join("\n");
+    throw new Error(`Invalid config at ${snapshot.path}\n${issues}`);
+  }
+  const next = mutator(snapshot.config);
+  await writeConfigFile(next);
+  return next;
+}
+
+export function resolveModelTarget(params: {
+  raw: string;
+  cfg: ClawdbotConfig;
+}): { provider: string; model: string } {
+  const aliasIndex = buildModelAliasIndex({
+    cfg: params.cfg,
+    defaultProvider: DEFAULT_PROVIDER,
+  });
+  const resolved = resolveModelRefFromString({
+    raw: params.raw,
+    defaultProvider: DEFAULT_PROVIDER,
+    aliasIndex,
+  });
+  if (!resolved) {
+    throw new Error(`Invalid model reference: ${params.raw}`);
+  }
+  return resolved.ref;
+}
+
+export function buildAllowlistSet(cfg: ClawdbotConfig): Set<string> {
+  const allowed = new Set<string>();
+  for (const raw of cfg.agent?.allowedModels ?? []) {
+    const parsed = parseModelRef(String(raw ?? ""), DEFAULT_PROVIDER);
+    if (!parsed) continue;
+    allowed.add(modelKey(parsed.provider, parsed.model));
+  }
+  return allowed;
+}
+
+export function normalizeAlias(alias: string): string {
+  const trimmed = alias.trim();
+  if (!trimmed) throw new Error("Alias cannot be empty.");
+  if (!/^[A-Za-z0-9_.:-]+$/.test(trimmed)) {
+    throw new Error(
+      "Alias must use letters, numbers, dots, underscores, colons, or dashes.",
+    );
+  }
+  return trimmed;
+}
+
+export { modelKey };
+export { DEFAULT_MODEL, DEFAULT_PROVIDER };

src/config/schema.ts

@@ -88,6 +88,7 @@ const FIELD_LABELS: Record<string, string> = {
   "gateway.reload.debounceMs": "Config Reload Debounce (ms)",
   "agent.workspace": "Workspace",
   "agent.model": "Default Model",
+  "agent.modelFallbacks": "Model Fallbacks",
   "ui.seamColor": "Accent Color",
   "browser.controlUrl": "Browser Control URL",
   "session.agentToAgent.maxPingPongTurns": "Agent-to-Agent Ping-Pong Turns",
@@ -111,6 +112,8 @@ const FIELD_HELP: Record<string, string> = {
     'Hot reload strategy for config changes ("hybrid" recommended).',
   "gateway.reload.debounceMs":
     "Debounce window (ms) before applying config changes.",
+  "agent.modelFallbacks":
+    "Ordered fallback models (provider/model). Used when the primary model fails.",
   "session.agentToAgent.maxPingPongTurns":
     "Max reply-back turns between requester and target (0–5).",
 };

src/config/sessions.ts

@@ -50,6 +50,7 @@ export type SessionEntry = {
   inputTokens?: number;
   outputTokens?: number;
   totalTokens?: number;
+  modelProvider?: string;
   model?: string;
   contextTokens?: number;
   displayName?: string;
@@ -335,6 +336,7 @@ export async function updateLastRoute(params: {
     inputTokens: existing?.inputTokens,
     outputTokens: existing?.outputTokens,
     totalTokens: existing?.totalTokens,
+    modelProvider: existing?.modelProvider,
     model: existing?.model,
     contextTokens: existing?.contextTokens,
     displayName: existing?.displayName,

src/config/types.ts

@@ -666,6 +666,8 @@ export type ClawdbotConfig = {
     allowedModels?: string[];
     /** Optional model aliases for /model (alias -> provider/model). */
     modelAliases?: Record<string, string>;
+    /** Ordered fallback models (provider/model). */
+    modelFallbacks?: string[];
     /** Optional display-only context window override (used for % in status UIs). */
     contextTokens?: number;
     /** Default thinking level when no /think directive is present. */

src/config/zod-schema.ts

@@ -366,6 +366,7 @@ export const ClawdbotSchema = z.object({
       workspace: z.string().optional(),
       allowedModels: z.array(z.string()).optional(),
       modelAliases: z.record(z.string(), z.string()).optional(),
+      modelFallbacks: z.array(z.string()).optional(),
       contextTokens: z.number().int().positive().optional(),
       thinkingDefault: z
         .union([

src/cron/isolated-agent.ts

@@ -10,6 +10,7 @@ import {
   resolveConfiguredModelRef,
   resolveThinkingDefault,
 } from "../agents/model-selection.js";
+import { runWithModelFallback } from "../agents/model-fallback.js";
 import { runEmbeddedPiAgent } from "../agents/pi-embedded.js";
 import { buildWorkspaceSkillSnapshot } from "../agents/skills.js";
 import {
@@ -264,6 +265,8 @@ export async function runCronIsolatedAgentTurn(params: {
   }
 
   let runResult: Awaited<ReturnType<typeof runEmbeddedPiAgent>>;
+  let fallbackProvider = provider;
+  let fallbackModel = model;
   try {
     const sessionFile = resolveSessionTranscriptPath(
       cronSession.sessionEntry.sessionId,
@@ -272,7 +275,12 @@ export async function runCronIsolatedAgentTurn(params: {
       sessionKey: params.sessionKey,
     });
     const surface = resolvedDelivery.channel;
-    runResult = await runEmbeddedPiAgent({
+    const fallbackResult = await runWithModelFallback({
+      cfg: params.cfg,
+      provider,
+      model,
+      run: (providerOverride, modelOverride) =>
+        runEmbeddedPiAgent({
           sessionId: cronSession.sessionEntry.sessionId,
           sessionKey: params.sessionKey,
           surface,
@@ -282,15 +290,19 @@ export async function runCronIsolatedAgentTurn(params: {
           skillsSnapshot,
           prompt: commandBody,
           lane: params.lane ?? "cron",
-      provider,
+          provider: providerOverride,
-      model,
+          model: modelOverride,
           thinkLevel,
           verboseLevel:
             (cronSession.sessionEntry.verboseLevel as "on" | "off" | undefined) ??
             (agentCfg?.verboseDefault as "on" | "off" | undefined),
           timeoutMs,
           runId: cronSession.sessionEntry.sessionId,
+        }),
     });
+    runResult = fallbackResult.result;
+    fallbackProvider = fallbackResult.provider;
+    fallbackModel = fallbackResult.model;
   } catch (err) {
     return { status: "error", error: String(err) };
   }
@@ -300,12 +312,16 @@ export async function runCronIsolatedAgentTurn(params: {
   // Update token+model fields in the session store.
   {
     const usage = runResult.meta.agentMeta?.usage;
-    const modelUsed = runResult.meta.agentMeta?.model ?? model;
+    const modelUsed =
+      runResult.meta.agentMeta?.model ?? fallbackModel ?? model;
+    const providerUsed =
+      runResult.meta.agentMeta?.provider ?? fallbackProvider ?? provider;
     const contextTokens =
       agentCfg?.contextTokens ??
       lookupContextTokens(modelUsed) ??
       DEFAULT_CONTEXT_TOKENS;
 
+    cronSession.sessionEntry.modelProvider = providerUsed;
     cronSession.sessionEntry.model = modelUsed;
     cronSession.sessionEntry.contextTokens = contextTokens;
     if (usage) {