feat: add coding-agent skill and anyBins gating

Co-authored-by: Sreekaran Srinath <ss@sreekaran.com>

docs/skills.md

@@ -61,6 +61,7 @@ Fields under `metadata.clawdis`:
 - `homepage` — optional URL shown as “Website” in the macOS Skills UI.
 - `os` — optional list of platforms (`darwin`, `linux`, `win32`). If set, the skill is only eligible on those OSes.
 - `requires.bins` — list; each must exist on `PATH`.
+- `requires.anyBins` — list; at least one must exist on `PATH`.
 - `requires.env` — list; env var must exist **or** be provided in config.
 - `requires.config` — list of `clawdis.json` paths that must be truthy.
 - `primaryEnv` — env var name associated with `skills.entries.<name>.apiKey`.

skills/coding-agent/SKILL.md

@@ -0,0 +1,78 @@
+---
+name: coding-agent
+description: Run Claude Code, Codex CLI, or OpenCode via tmux for resilient coding sessions.
+metadata: {"clawdis":{"emoji":"🧩","requires":{"bins":["tmux"],"anyBins":["claude","codex","opencode"]}}}
+---
+
+# Coding Agent (tmux-first)
+
+Use **tmux** for all coding-agent CLIs. Keep sessions resumable and logs visible.
+
+## Quick preflight
+
+```bash
+command -v claude codex opencode tmux
+```
+
+If none of `claude`, `codex`, `opencode` exist, stop and ask to install.
+
+## tmux baseline
+
+```bash
+# Create or attach
+tmux new -A -s coding-agent
+
+# Split panes
+tmux split-window -h
+tmux split-window -v
+
+# Leave running, detach
+tmux detach
+```
+
+## Claude Code
+
+Interactive (preferred in tmux):
+- `claude` — start session
+- `claude -c` — continue most recent
+- `claude -r ""` — picker
+- `claude -r <session_id>` — resume specific
+
+## Codex CLI
+
+One-shot (safe in tmux):
+- `codex exec "Write a Python function that ..."`
+- `codex exec --model gpt-4o "Complex task"`
+- `codex exec --model o3 "Reasoning-heavy task"`
+
+Interactive:
+- `codex "Your prompt"`
+- `codex resume`
+- `codex resume --last`
+- `codex resume --session <id>`
+
+Apply changes:
+- `codex apply`
+
+## OpenCode
+
+One-shot:
+- `opencode run "Write a Python function that ..."`
+- `opencode run -m anthropic/claude-sonnet-4-5 "Complex task"`
+- `opencode run -m openai/gpt-5.2 "Coding task"`
+- `opencode run -m google/gemini-2.5-pro "Research task"`
+
+Interactive:
+- `opencode`
+- `opencode -c`
+- `opencode -s <session-id>`
+
+Session management:
+- `opencode session list`
+- `opencode export [sessionID]`
+- `opencode import <file>`
+
+## Notes
+
+- Prefer **tmux** even for one-shot runs; keep history + recovery.
+- For auth, run the tool’s login flow in tmux (`claude`, `codex login`, `opencode auth`).

src/agents/skills.test.ts

@@ -215,6 +215,12 @@ describe("buildWorkspaceSkillsPrompt", () => {
       description: "Needs a bin",
       metadata: '{"clawdis":{"requires":{"bins":["fakebin"]}}}',
     });
+    await writeSkill({
+      dir: path.join(skillsDir, "anybin-skill"),
+      name: "anybin-skill",
+      description: "Needs any bin",
+      metadata: '{"clawdis":{"requires":{"anyBins":["missingbin","fakebin"]}}}',
+    });
     await writeSkill({
       dir: path.join(skillsDir, "config-skill"),
       name: "config-skill",
@@ -242,6 +248,7 @@ describe("buildWorkspaceSkillsPrompt", () => {
       expect(defaultPrompt).toContain("always-skill");
       expect(defaultPrompt).toContain("config-skill");
       expect(defaultPrompt).not.toContain("bin-skill");
+      expect(defaultPrompt).not.toContain("anybin-skill");
       expect(defaultPrompt).not.toContain("env-skill");
 
       await fs.mkdir(binDir, { recursive: true });
@@ -258,6 +265,7 @@ describe("buildWorkspaceSkillsPrompt", () => {
         },
       });
       expect(gatedPrompt).toContain("bin-skill");
+      expect(gatedPrompt).toContain("anybin-skill");
       expect(gatedPrompt).toContain("env-skill");
       expect(gatedPrompt).toContain("always-skill");
       expect(gatedPrompt).not.toContain("config-skill");

src/agents/skills.ts

@@ -30,6 +30,7 @@ export type ClawdisSkillMetadata = {
   os?: string[];
   requires?: {
     bins?: string[];
+    anyBins?: string[];
     env?: string[];
     config?: string[];
   };
@@ -307,6 +308,7 @@ function resolveClawdisMetadata(
       requires: requiresRaw
         ? {
             bins: normalizeStringList(requiresRaw.bins),
+            anyBins: normalizeStringList(requiresRaw.anyBins),
             env: normalizeStringList(requiresRaw.env),
             config: normalizeStringList(requiresRaw.config),
           }
@@ -347,6 +349,11 @@ function shouldIncludeSkill(params: {
       if (!hasBinary(bin)) return false;
     }
   }
+  const requiredAnyBins = entry.clawdis?.requires?.anyBins ?? [];
+  if (requiredAnyBins.length > 0) {
+    const anyFound = requiredAnyBins.some((bin) => hasBinary(bin));
+    if (!anyFound) return false;
+  }
 
   const requiredEnv = entry.clawdis?.requires?.env ?? [];
   if (requiredEnv.length > 0) {