refactor(channels): unify target parsing

src/channels/plugins/directory-config.ts

@@ -4,7 +4,7 @@ import { resolveSlackAccount } from "../../slack/accounts.js";
 import { resolveDiscordAccount } from "../../discord/accounts.js";
 import { resolveTelegramAccount } from "../../telegram/accounts.js";
 import { resolveWhatsAppAccount } from "../../web/accounts.js";
-import { normalizeSlackMessagingTarget } from "./normalize-target.js";
+import { normalizeSlackMessagingTarget } from "./normalize/slack.js";
 import { isWhatsAppGroupJid, normalizeWhatsAppTarget } from "../../whatsapp/normalize.js";
 
 export type DirectoryConfigParams = {

src/channels/plugins/discord.ts

@@ -26,7 +26,10 @@ import {
 } from "./config-helpers.js";
 import { resolveDiscordGroupRequireMention } from "./group-mentions.js";
 import { formatPairingApproveHint } from "./helpers.js";
-import { looksLikeDiscordTargetId, normalizeDiscordMessagingTarget } from "./normalize-target.js";
+import {
+  looksLikeDiscordTargetId,
+  normalizeDiscordMessagingTarget,
+} from "./normalize/discord.js";
 import { discordOnboardingAdapter } from "./onboarding/discord.js";
 import { PAIRING_APPROVED_MESSAGE } from "./pairing-message.js";
 import {

src/channels/plugins/normalize-target.ts

@@ -1,104 +0,0 @@
-import { parseDiscordTarget } from "../../discord/targets.js";
-import { parseSlackTarget } from "../../slack/targets.js";
-import { normalizeWhatsAppTarget } from "../../whatsapp/normalize.js";
-
-export function normalizeSlackMessagingTarget(raw: string): string | undefined {
-  const target = parseSlackTarget(raw, { defaultKind: "channel" });
-  return target?.normalized;
-}
-
-export function looksLikeSlackTargetId(raw: string): boolean {
-  const trimmed = raw.trim();
-  if (!trimmed) return false;
-  if (/^<@([A-Z0-9]+)>$/i.test(trimmed)) return true;
-  if (/^(user|channel):/i.test(trimmed)) return true;
-  if (/^slack:/i.test(trimmed)) return true;
-  if (/^[@#]/.test(trimmed)) return true;
-  return /^[CUWGD][A-Z0-9]{8,}$/i.test(trimmed);
-}
-
-export function normalizeDiscordMessagingTarget(raw: string): string | undefined {
-  // Default bare IDs to channels so routing is stable across tool actions.
-  const target = parseDiscordTarget(raw, { defaultKind: "channel" });
-  return target?.normalized;
-}
-
-export function looksLikeDiscordTargetId(raw: string): boolean {
-  const trimmed = raw.trim();
-  if (!trimmed) return false;
-  if (/^<@!?\d+>$/.test(trimmed)) return true;
-  if (/^(user|channel|discord):/i.test(trimmed)) return true;
-  if (/^\d{6,}$/.test(trimmed)) return true;
-  return false;
-}
-
-export function normalizeTelegramMessagingTarget(raw: string): string | undefined {
-  const trimmed = raw.trim();
-  if (!trimmed) return undefined;
-  let normalized = trimmed;
-  if (normalized.startsWith("telegram:")) {
-    normalized = normalized.slice("telegram:".length).trim();
-  } else if (normalized.startsWith("tg:")) {
-    normalized = normalized.slice("tg:".length).trim();
-  }
-  if (!normalized) return undefined;
-  const tmeMatch =
-    /^https?:\/\/t\.me\/([A-Za-z0-9_]+)$/i.exec(normalized) ??
-    /^t\.me\/([A-Za-z0-9_]+)$/i.exec(normalized);
-  if (tmeMatch?.[1]) normalized = `@${tmeMatch[1]}`;
-  if (!normalized) return undefined;
-  return `telegram:${normalized}`.toLowerCase();
-}
-
-export function looksLikeTelegramTargetId(raw: string): boolean {
-  const trimmed = raw.trim();
-  if (!trimmed) return false;
-  if (/^(telegram|tg):/i.test(trimmed)) return true;
-  if (trimmed.startsWith("@")) return true;
-  return /^-?\d{6,}$/.test(trimmed);
-}
-
-export function normalizeSignalMessagingTarget(raw: string): string | undefined {
-  const trimmed = raw.trim();
-  if (!trimmed) return undefined;
-  let normalized = trimmed;
-  if (normalized.toLowerCase().startsWith("signal:")) {
-    normalized = normalized.slice("signal:".length).trim();
-  }
-  if (!normalized) return undefined;
-  const lower = normalized.toLowerCase();
-  if (lower.startsWith("group:")) {
-    const id = normalized.slice("group:".length).trim();
-    return id ? `group:${id}`.toLowerCase() : undefined;
-  }
-  if (lower.startsWith("username:")) {
-    const id = normalized.slice("username:".length).trim();
-    return id ? `username:${id}`.toLowerCase() : undefined;
-  }
-  if (lower.startsWith("u:")) {
-    const id = normalized.slice("u:".length).trim();
-    return id ? `username:${id}`.toLowerCase() : undefined;
-  }
-  return normalized.toLowerCase();
-}
-
-export function looksLikeSignalTargetId(raw: string): boolean {
-  const trimmed = raw.trim();
-  if (!trimmed) return false;
-  if (/^(signal:)?(group:|username:|u:)/i.test(trimmed)) return true;
-  return /^\+?\d{3,}$/.test(trimmed);
-}
-
-export function normalizeWhatsAppMessagingTarget(raw: string): string | undefined {
-  const trimmed = raw.trim();
-  if (!trimmed) return undefined;
-  return normalizeWhatsAppTarget(trimmed) ?? undefined;
-}
-
-export function looksLikeWhatsAppTargetId(raw: string): boolean {
-  const trimmed = raw.trim();
-  if (!trimmed) return false;
-  if (/^whatsapp:/i.test(trimmed)) return true;
-  if (trimmed.includes("@")) return true;
-  return /^\+?\d{3,}$/.test(trimmed);
-}

src/channels/plugins/normalize/discord.ts

@@ -0,0 +1,16 @@
+import { parseDiscordTarget } from "../../../discord/targets.js";
+
+export function normalizeDiscordMessagingTarget(raw: string): string | undefined {
+  // Default bare IDs to channels so routing is stable across tool actions.
+  const target = parseDiscordTarget(raw, { defaultKind: "channel" });
+  return target?.normalized;
+}
+
+export function looksLikeDiscordTargetId(raw: string): boolean {
+  const trimmed = raw.trim();
+  if (!trimmed) return false;
+  if (/^<@!?\d+>$/.test(trimmed)) return true;
+  if (/^(user|channel|discord):/i.test(trimmed)) return true;
+  if (/^\d{6,}$/.test(trimmed)) return true;
+  return false;
+}

src/channels/plugins/normalize/signal.ts

@@ -0,0 +1,30 @@
+export function normalizeSignalMessagingTarget(raw: string): string | undefined {
+  const trimmed = raw.trim();
+  if (!trimmed) return undefined;
+  let normalized = trimmed;
+  if (normalized.toLowerCase().startsWith("signal:")) {
+    normalized = normalized.slice("signal:".length).trim();
+  }
+  if (!normalized) return undefined;
+  const lower = normalized.toLowerCase();
+  if (lower.startsWith("group:")) {
+    const id = normalized.slice("group:".length).trim();
+    return id ? `group:${id}`.toLowerCase() : undefined;
+  }
+  if (lower.startsWith("username:")) {
+    const id = normalized.slice("username:".length).trim();
+    return id ? `username:${id}`.toLowerCase() : undefined;
+  }
+  if (lower.startsWith("u:")) {
+    const id = normalized.slice("u:".length).trim();
+    return id ? `username:${id}`.toLowerCase() : undefined;
+  }
+  return normalized.toLowerCase();
+}
+
+export function looksLikeSignalTargetId(raw: string): boolean {
+  const trimmed = raw.trim();
+  if (!trimmed) return false;
+  if (/^(signal:)?(group:|username:|u:)/i.test(trimmed)) return true;
+  return /^\+?\d{3,}$/.test(trimmed);
+}

src/channels/plugins/normalize/slack.ts

@@ -0,0 +1,16 @@
+import { parseSlackTarget } from "../../../slack/targets.js";
+
+export function normalizeSlackMessagingTarget(raw: string): string | undefined {
+  const target = parseSlackTarget(raw, { defaultKind: "channel" });
+  return target?.normalized;
+}
+
+export function looksLikeSlackTargetId(raw: string): boolean {
+  const trimmed = raw.trim();
+  if (!trimmed) return false;
+  if (/^<@([A-Z0-9]+)>$/i.test(trimmed)) return true;
+  if (/^(user|channel):/i.test(trimmed)) return true;
+  if (/^slack:/i.test(trimmed)) return true;
+  if (/^[@#]/.test(trimmed)) return true;
+  return /^[CUWGD][A-Z0-9]{8,}$/i.test(trimmed);
+}

src/channels/plugins/normalize/telegram.ts

@@ -0,0 +1,25 @@
+export function normalizeTelegramMessagingTarget(raw: string): string | undefined {
+  const trimmed = raw.trim();
+  if (!trimmed) return undefined;
+  let normalized = trimmed;
+  if (normalized.startsWith("telegram:")) {
+    normalized = normalized.slice("telegram:".length).trim();
+  } else if (normalized.startsWith("tg:")) {
+    normalized = normalized.slice("tg:".length).trim();
+  }
+  if (!normalized) return undefined;
+  const tmeMatch =
+    /^https?:\/\/t\.me\/([A-Za-z0-9_]+)$/i.exec(normalized) ??
+    /^t\.me\/([A-Za-z0-9_]+)$/i.exec(normalized);
+  if (tmeMatch?.[1]) normalized = `@${tmeMatch[1]}`;
+  if (!normalized) return undefined;
+  return `telegram:${normalized}`.toLowerCase();
+}
+
+export function looksLikeTelegramTargetId(raw: string): boolean {
+  const trimmed = raw.trim();
+  if (!trimmed) return false;
+  if (/^(telegram|tg):/i.test(trimmed)) return true;
+  if (trimmed.startsWith("@")) return true;
+  return /^-?\d{6,}$/.test(trimmed);
+}

src/channels/plugins/normalize/whatsapp.ts

@@ -0,0 +1,15 @@
+import { normalizeWhatsAppTarget } from "../../../whatsapp/normalize.js";
+
+export function normalizeWhatsAppMessagingTarget(raw: string): string | undefined {
+  const trimmed = raw.trim();
+  if (!trimmed) return undefined;
+  return normalizeWhatsAppTarget(trimmed) ?? undefined;
+}
+
+export function looksLikeWhatsAppTargetId(raw: string): boolean {
+  const trimmed = raw.trim();
+  if (!trimmed) return false;
+  if (/^whatsapp:/i.test(trimmed)) return true;
+  if (trimmed.includes("@")) return true;
+  return /^\+?\d{3,}$/.test(trimmed);
+}

src/channels/plugins/signal.ts

@@ -18,7 +18,10 @@ import {
 } from "./config-helpers.js";
 import { formatPairingApproveHint } from "./helpers.js";
 import { resolveChannelMediaMaxBytes } from "./media-limits.js";
-import { looksLikeSignalTargetId, normalizeSignalMessagingTarget } from "./normalize-target.js";
+import {
+  looksLikeSignalTargetId,
+  normalizeSignalMessagingTarget,
+} from "./normalize/signal.js";
 import { signalOnboardingAdapter } from "./onboarding/signal.js";
 import { PAIRING_APPROVED_MESSAGE } from "./pairing-message.js";
 import {

src/channels/plugins/slack.ts

@@ -20,7 +20,7 @@ import {
 } from "./config-helpers.js";
 import { resolveSlackGroupRequireMention } from "./group-mentions.js";
 import { formatPairingApproveHint } from "./helpers.js";
-import { looksLikeSlackTargetId, normalizeSlackMessagingTarget } from "./normalize-target.js";
+import { looksLikeSlackTargetId, normalizeSlackMessagingTarget } from "./normalize/slack.js";
 import { slackOnboardingAdapter } from "./onboarding/slack.js";
 import { PAIRING_APPROVED_MESSAGE } from "./pairing-message.js";
 import {

src/channels/plugins/telegram.ts

@@ -26,7 +26,10 @@ import {
 } from "./config-helpers.js";
 import { resolveTelegramGroupRequireMention } from "./group-mentions.js";
 import { formatPairingApproveHint } from "./helpers.js";
-import { looksLikeTelegramTargetId, normalizeTelegramMessagingTarget } from "./normalize-target.js";
+import {
+  looksLikeTelegramTargetId,
+  normalizeTelegramMessagingTarget,
+} from "./normalize/telegram.js";
 import { telegramOnboardingAdapter } from "./onboarding/telegram.js";
 import { PAIRING_APPROVED_MESSAGE } from "./pairing-message.js";
 import {

src/channels/plugins/whatsapp.ts

@@ -26,7 +26,10 @@ import { buildChannelConfigSchema } from "./config-schema.js";
 import { createWhatsAppLoginTool } from "./agent-tools/whatsapp-login.js";
 import { resolveWhatsAppGroupRequireMention } from "./group-mentions.js";
 import { formatPairingApproveHint } from "./helpers.js";
-import { looksLikeWhatsAppTargetId, normalizeWhatsAppMessagingTarget } from "./normalize-target.js";
+import {
+  looksLikeWhatsAppTargetId,
+  normalizeWhatsAppMessagingTarget,
+} from "./normalize/whatsapp.js";
 import { whatsappOnboardingAdapter } from "./onboarding/whatsapp.js";
 import {
   applyAccountNameToChannelSection,

src/channels/targets.test.ts

@@ -0,0 +1,42 @@
+import { describe, expect, it } from "vitest";
+
+import { buildMessagingTarget, ensureTargetId, requireTargetKind } from "./targets.js";
+
+describe("ensureTargetId", () => {
+  it("returns the candidate when it matches", () => {
+    expect(
+      ensureTargetId({
+        candidate: "U123",
+        pattern: /^[A-Z0-9]+$/i,
+        errorMessage: "bad",
+      }),
+    ).toBe("U123");
+  });
+
+  it("throws with the provided message on mismatch", () => {
+    expect(() =>
+      ensureTargetId({
+        candidate: "not-ok",
+        pattern: /^[A-Z0-9]+$/i,
+        errorMessage: "Bad target",
+      }),
+    ).toThrow(/Bad target/);
+  });
+});
+
+describe("requireTargetKind", () => {
+  it("returns the target id when the kind matches", () => {
+    const target = buildMessagingTarget("channel", "C123", "C123");
+    expect(requireTargetKind({ platform: "Slack", target, kind: "channel" })).toBe("C123");
+  });
+
+  it("throws when the kind is missing or mismatched", () => {
+    expect(() => requireTargetKind({ platform: "Slack", target: undefined, kind: "channel" })).toThrow(
+      /Slack channel id is required/,
+    );
+    const target = buildMessagingTarget("user", "U123", "U123");
+    expect(() => requireTargetKind({ platform: "Slack", target, kind: "channel" })).toThrow(
+      /Slack channel id is required/,
+    );
+  });
+});

src/channels/targets.ts

@@ -0,0 +1,56 @@
+export type MessagingTargetKind = "user" | "channel";
+
+export type MessagingTarget = {
+  kind: MessagingTargetKind;
+  id: string;
+  raw: string;
+  normalized: string;
+};
+
+export type MessagingTargetParseOptions = {
+  defaultKind?: MessagingTargetKind;
+  ambiguousMessage?: string;
+};
+
+export function normalizeTargetId(kind: MessagingTargetKind, id: string): string {
+  return `${kind}:${id}`.toLowerCase();
+}
+
+export function buildMessagingTarget(
+  kind: MessagingTargetKind,
+  id: string,
+  raw: string,
+): MessagingTarget {
+  return {
+    kind,
+    id,
+    raw,
+    normalized: normalizeTargetId(kind, id),
+  };
+}
+
+export function ensureTargetId(params: {
+  candidate: string;
+  pattern: RegExp;
+  errorMessage: string;
+}): string {
+  if (!params.pattern.test(params.candidate)) {
+    throw new Error(params.errorMessage);
+  }
+  return params.candidate;
+}
+
+export function requireTargetKind(params: {
+  platform: string;
+  target: MessagingTarget | undefined;
+  kind: MessagingTargetKind;
+}): string {
+  const kindLabel = params.kind;
+  if (!params.target) {
+    throw new Error(`${params.platform} ${kindLabel} id is required.`);
+  }
+  if (params.target.kind !== params.kind) {
+    throw new Error(`${params.platform} ${kindLabel} id is required (use ${kindLabel}:<id>).`);
+  }
+  return params.target.id;
+}

src/discord/targets.test.ts

@@ -1,6 +1,6 @@
 import { describe, expect, it } from "vitest";
 
-import { normalizeDiscordMessagingTarget } from "../channels/plugins/normalize-target.js";
+import { normalizeDiscordMessagingTarget } from "../channels/plugins/normalize/discord.js";
 import { parseDiscordTarget, resolveDiscordChannelId } from "./targets.js";
 
 describe("parseDiscordTarget", () => {

src/discord/targets.ts

@@ -1,29 +1,17 @@
-export type DiscordTargetKind = "user" | "channel";
+import {
+  buildMessagingTarget,
+  ensureTargetId,
+  requireTargetKind,
+  type MessagingTarget,
+  type MessagingTargetKind,
+  type MessagingTargetParseOptions,
+} from "../channels/targets.js";
 
-export type DiscordTarget = {
-  kind: DiscordTargetKind;
-  id: string;
-  raw: string;
-  normalized: string;
-};
+export type DiscordTargetKind = MessagingTargetKind;
 
-type DiscordTargetParseOptions = {
-  defaultKind?: DiscordTargetKind;
-  ambiguousMessage?: string;
-};
+export type DiscordTarget = MessagingTarget;
 
-function normalizeTargetId(kind: DiscordTargetKind, id: string) {
-  return `${kind}:${id}`.toLowerCase();
-}
-
-function buildTarget(kind: DiscordTargetKind, id: string, raw: string): DiscordTarget {
-  return {
-    kind,
-    id,
-    raw,
-    normalized: normalizeTargetId(kind, id),
-  };
-}
+type DiscordTargetParseOptions = MessagingTargetParseOptions;
 
 export function parseDiscordTarget(
   raw: string,
@@ -33,46 +21,42 @@ export function parseDiscordTarget(
   if (!trimmed) return undefined;
   const mentionMatch = trimmed.match(/^<@!?(\d+)>$/);
   if (mentionMatch) {
-    return buildTarget("user", mentionMatch[1], trimmed);
+    return buildMessagingTarget("user", mentionMatch[1], trimmed);
   }
   if (trimmed.startsWith("user:")) {
     const id = trimmed.slice("user:".length).trim();
-    return id ? buildTarget("user", id, trimmed) : undefined;
+    return id ? buildMessagingTarget("user", id, trimmed) : undefined;
   }
   if (trimmed.startsWith("channel:")) {
     const id = trimmed.slice("channel:".length).trim();
-    return id ? buildTarget("channel", id, trimmed) : undefined;
+    return id ? buildMessagingTarget("channel", id, trimmed) : undefined;
   }
   if (trimmed.startsWith("discord:")) {
     const id = trimmed.slice("discord:".length).trim();
-    return id ? buildTarget("user", id, trimmed) : undefined;
+    return id ? buildMessagingTarget("user", id, trimmed) : undefined;
   }
   if (trimmed.startsWith("@")) {
     const candidate = trimmed.slice(1).trim();
-    if (!/^\d+$/.test(candidate)) {
-      throw new Error("Discord DMs require a user id (use user:<id> or a <@id> mention)");
-    }
-    return buildTarget("user", candidate, trimmed);
+    const id = ensureTargetId({
+      candidate,
+      pattern: /^\d+$/,
+      errorMessage: "Discord DMs require a user id (use user:<id> or a <@id> mention)",
+    });
+    return buildMessagingTarget("user", id, trimmed);
   }
   if (/^\d+$/.test(trimmed)) {
     if (options.defaultKind) {
-      return buildTarget(options.defaultKind, trimmed, trimmed);
+      return buildMessagingTarget(options.defaultKind, trimmed, trimmed);
     }
     throw new Error(
       options.ambiguousMessage ??
         `Ambiguous Discord recipient "${trimmed}". Use "user:${trimmed}" for DMs or "channel:${trimmed}" for channel messages.`,
     );
   }
-  return buildTarget("channel", trimmed, trimmed);
+  return buildMessagingTarget("channel", trimmed, trimmed);
 }
 
 export function resolveDiscordChannelId(raw: string): string {
   const target = parseDiscordTarget(raw, { defaultKind: "channel" });
-  if (!target) {
-    throw new Error("Discord channel id is required.");
-  }
-  if (target.kind !== "channel") {
-    throw new Error("Discord channel id is required (use channel:<id>).");
-  }
-  return target.id;
+  return requireTargetKind({ platform: "Discord", target, kind: "channel" });
 }

src/slack/targets.test.ts

@@ -1,6 +1,6 @@
 import { describe, expect, it } from "vitest";
 
-import { normalizeSlackMessagingTarget } from "../channels/plugins/normalize-target.js";
+import { normalizeSlackMessagingTarget } from "../channels/plugins/normalize/slack.js";
 import { parseSlackTarget, resolveSlackChannelId } from "./targets.js";
 
 describe("parseSlackTarget", () => {

src/slack/targets.ts

@@ -1,28 +1,17 @@
-export type SlackTargetKind = "user" | "channel";
+import {
+  buildMessagingTarget,
+  ensureTargetId,
+  requireTargetKind,
+  type MessagingTarget,
+  type MessagingTargetKind,
+  type MessagingTargetParseOptions,
+} from "../channels/targets.js";
 
-export type SlackTarget = {
-  kind: SlackTargetKind;
-  id: string;
-  raw: string;
-  normalized: string;
-};
+export type SlackTargetKind = MessagingTargetKind;
 
-type SlackTargetParseOptions = {
-  defaultKind?: SlackTargetKind;
-};
+export type SlackTarget = MessagingTarget;
 
-function normalizeTargetId(kind: SlackTargetKind, id: string) {
-  return `${kind}:${id}`.toLowerCase();
-}
-
-function buildTarget(kind: SlackTargetKind, id: string, raw: string): SlackTarget {
-  return {
-    kind,
-    id,
-    raw,
-    normalized: normalizeTargetId(kind, id),
-  };
-}
+type SlackTargetParseOptions = MessagingTargetParseOptions;
 
 export function parseSlackTarget(
   raw: string,
@@ -32,47 +21,45 @@ export function parseSlackTarget(
   if (!trimmed) return undefined;
   const mentionMatch = trimmed.match(/^<@([A-Z0-9]+)>$/i);
   if (mentionMatch) {
-    return buildTarget("user", mentionMatch[1], trimmed);
+    return buildMessagingTarget("user", mentionMatch[1], trimmed);
   }
   if (trimmed.startsWith("user:")) {
     const id = trimmed.slice("user:".length).trim();
-    return id ? buildTarget("user", id, trimmed) : undefined;
+    return id ? buildMessagingTarget("user", id, trimmed) : undefined;
   }
   if (trimmed.startsWith("channel:")) {
     const id = trimmed.slice("channel:".length).trim();
-    return id ? buildTarget("channel", id, trimmed) : undefined;
+    return id ? buildMessagingTarget("channel", id, trimmed) : undefined;
   }
   if (trimmed.startsWith("slack:")) {
     const id = trimmed.slice("slack:".length).trim();
-    return id ? buildTarget("user", id, trimmed) : undefined;
+    return id ? buildMessagingTarget("user", id, trimmed) : undefined;
   }
   if (trimmed.startsWith("@")) {
     const candidate = trimmed.slice(1).trim();
-    if (!/^[A-Z0-9]+$/i.test(candidate)) {
-      throw new Error("Slack DMs require a user id (use user:<id> or <@id>)");
-    }
-    return buildTarget("user", candidate, trimmed);
+    const id = ensureTargetId({
+      candidate,
+      pattern: /^[A-Z0-9]+$/i,
+      errorMessage: "Slack DMs require a user id (use user:<id> or <@id>)",
+    });
+    return buildMessagingTarget("user", id, trimmed);
   }
   if (trimmed.startsWith("#")) {
     const candidate = trimmed.slice(1).trim();
-    if (!/^[A-Z0-9]+$/i.test(candidate)) {
-      throw new Error("Slack channels require a channel id (use channel:<id>)");
-    }
-    return buildTarget("channel", candidate, trimmed);
+    const id = ensureTargetId({
+      candidate,
+      pattern: /^[A-Z0-9]+$/i,
+      errorMessage: "Slack channels require a channel id (use channel:<id>)",
+    });
+    return buildMessagingTarget("channel", id, trimmed);
   }
   if (options.defaultKind) {
-    return buildTarget(options.defaultKind, trimmed, trimmed);
+    return buildMessagingTarget(options.defaultKind, trimmed, trimmed);
   }
-  return buildTarget("channel", trimmed, trimmed);
+  return buildMessagingTarget("channel", trimmed, trimmed);
 }
 
 export function resolveSlackChannelId(raw: string): string {
   const target = parseSlackTarget(raw, { defaultKind: "channel" });
-  if (!target) {
-    throw new Error("Slack channel id is required.");
-  }
-  if (target.kind !== "channel") {
-    throw new Error("Slack channel id is required (use channel:<id>).");
-  }
-  return target.id;
+  return requireTargetKind({ platform: "Slack", target, kind: "channel" });
 }