diff --git a/document-release/SKILL.md.tmpl b/document-release/SKILL.md.tmpl
index 5d236ae2..6b1fb7e3 100644
--- a/document-release/SKILL.md.tmpl
+++ b/document-release/SKILL.md.tmpl
@@ -280,7 +280,7 @@ committing.
 git commit -m "$(cat <<'EOF'
 docs: update project documentation for vX.Y.Z.W
 
-Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
+{{CO_AUTHOR_TRAILER}}
 EOF
 )"
 ```
diff --git a/scripts/resolvers/index.ts b/scripts/resolvers/index.ts
index 9e9b9596..d4536312 100644
--- a/scripts/resolvers/index.ts
+++ b/scripts/resolvers/index.ts
@@ -12,7 +12,7 @@ import { generateCommandReference, generateSnapshotFlags, generateBrowseSetup }
 import { generateDesignMethodology, generateDesignHardRules, generateDesignOutsideVoices, generateDesignReviewLite, generateDesignSketch } from './design';
 import { generateTestBootstrap, generateTestCoverageAuditPlan, generateTestCoverageAuditShip, generateTestCoverageAuditReview } from './testing';
 import { generateReviewDashboard, generatePlanFileReviewReport, generateSpecReviewLoop, generateBenefitsFrom, generateCodexSecondOpinion, generateAdversarialStep, generateCodexPlanReview, generatePlanCompletionAuditShip, generatePlanCompletionAuditReview, generatePlanVerificationExec } from './review';
-import { generateSlugEval, generateSlugSetup, generateBaseBranchDetect, generateDeployBootstrap, generateQAMethodology } from './utility';
+import { generateSlugEval, generateSlugSetup, generateBaseBranchDetect, generateDeployBootstrap, generateQAMethodology, generateCoAuthorTrailer } from './utility';
 
 export const RESOLVERS: Record<string, (ctx: TemplateContext) => string> = {
   SLUG_EVAL: generateSlugEval,
@@ -44,4 +44,5 @@ export const RESOLVERS: Record<string, (ctx: TemplateContext) => string> = {
   PLAN_COMPLETION_AUDIT_SHIP: generatePlanCompletionAuditShip,
   PLAN_COMPLETION_AUDIT_REVIEW: generatePlanCompletionAuditReview,
   PLAN_VERIFICATION_EXEC: generatePlanVerificationExec,
+  CO_AUTHOR_TRAILER: generateCoAuthorTrailer,
 };
diff --git a/scripts/resolvers/utility.ts b/scripts/resolvers/utility.ts
index 6cd912f2..574a11f2 100644
--- a/scripts/resolvers/utility.ts
+++ b/scripts/resolvers/utility.ts
@@ -364,3 +364,10 @@ Minimum 0 per category.
 11. **Show screenshots to the user.** After every \`$B screenshot\`, \`$B snapshot -a -o\`, or \`$B responsive\` command, use the Read tool on the output file(s) so the user can see them inline. For \`responsive\` (3 files), Read all three. This is critical — without it, screenshots are invisible to the user.
 12. **Never refuse to use the browser.** When the user invokes /qa or /qa-only, they are requesting browser-based testing. Never suggest evals, unit tests, or other alternatives as a substitute. Even if the diff appears to have no UI changes, backend changes affect app behavior — always open the browser and test.`;
 }
+
+export function generateCoAuthorTrailer(ctx: TemplateContext): string {
+  if (ctx.host === 'codex') {
+    return 'Co-Authored-By: OpenAI Codex <noreply@openai.com>';
+  }
+  return 'Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>';
+}
diff --git a/ship/SKILL.md.tmpl b/ship/SKILL.md.tmpl
index 7f545cd9..ea031661 100644
--- a/ship/SKILL.md.tmpl
+++ b/ship/SKILL.md.tmpl
@@ -443,7 +443,7 @@ Save this summary — it goes into the PR body in Step 8.
 git commit -m "$(cat <<'EOF'
 chore: bump version and changelog (vX.Y.Z.W)
 
-Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
+{{CO_AUTHOR_TRAILER}}
 EOF
 )"
 ```