docs(agents): AGENTS.md is the single entry point; CLAUDE.md removed

.gitignore

@@ -16,9 +16,8 @@ extension/coverage/
 extension/.fallow/
 extension/.eslintcache
 
-# Share this project's agent entry points despite user-global ignore rules
+# Share this project's agent entry point despite user-global ignore rules
 !/AGENTS.md
-!/CLAUDE.md
 
 # Share only the project compaction hook; keep other local Codex state private.
 !/.codex/

AGENTS.md

@@ -1,5 +1,7 @@
 # codebook agent instructions
 
+This file is the single operational entry point for every coding agent: Codex and Claude Code (v2.1.281 or later) load it as the project instructions. Keep agent instructions here; a `CLAUDE.md`, `.claude/CLAUDE.md` or `CLAUDE.local.md` in the repository or a directory above it makes Claude Code read that file instead of this one.
+
 ## Mandatory entry
 
 Before planning, implementation or runtime trials:
@@ -45,7 +47,7 @@ The driving agent owns state, cycle selection and completion claims; GStack supp
 
 **Chain.** One bounded cycle at a time toward the complete product. After each merge, `/spec` (with the plan reviews the scope needs) writes the next cycle's Issue. Work on a `codex/` branch; keep existing edits; reuse a fitting checkout. Each cycle: review by the local CodeRabbit CLI and `open-code-review-delegate`, `/ship` as a PR, required CI, a separate exact-HEAD gate, then the merge as its own step with `--match-head-commit`. A large cycle may use up to three PRs (`cycle100-pt1`, `cycle100-pt2`, …), each passing reviews, CI and the gate alone, merged in order; the Issue closes after the last. Codex automatic review is off: no Codex cloud step. PR bodies carry no `@coderabbitai ignore` (owner, 2026-10-05).
 
-**Delivery parameters.** The merge is a squash merge: `gh pr merge <n> --squash --match-head-commit <sha>`. `/ship`'s documentation candidate (`gstack-docs-candidate snapshot`) takes the kept documents as `--docs` roots: AGENTS.md, CHANGELOG.md, CLAUDE.md, PRODUCT_GOAL.md, README.md, `extension/README.md`, `extension/skills/codebook/SKILL.md` and the v9 PNG. CI packages the extension with `node extension/scripts/package.mjs --out artifacts/packages/codebook.vsix` and checks it with `node extension/scripts/check-package.mjs artifacts/packages/codebook.vsix` (`package.yml`). A release commit changes one test line besides the version files and CHANGELOG.md, the expected version in `extension/scripts/tests/package.test.mjs`; `/ship`'s Step 16 counts that edit as release metadata, not as a change to the reviewed tree.
+**Delivery parameters.** The merge is a squash merge: `gh pr merge <n> --squash --match-head-commit <sha>`. `/ship`'s documentation candidate (`gstack-docs-candidate snapshot`) takes the kept documents as `--docs` roots: AGENTS.md, CHANGELOG.md, PRODUCT_GOAL.md, README.md, `extension/README.md`, `extension/skills/codebook/SKILL.md` and the v9 PNG. CI packages the extension with `node extension/scripts/package.mjs --out artifacts/packages/codebook.vsix` and checks it with `node extension/scripts/check-package.mjs artifacts/packages/codebook.vsix` (`package.yml`). A release commit changes one test line besides the version files and CHANGELOG.md, the expected version in `extension/scripts/tests/package.test.mjs`; `/ship`'s Step 16 counts that edit as release metadata, not as a change to the reviewed tree.
 
 **Background work.** `node extension/scripts/watch-background.mjs` (from the directory Claude Code started in, else with `--project <that directory>`) lists the current Claude Code session's background tasks and subagents (its `CLAUDE_CODE_SESSION_ID`), each with the time of its last output, and marks those silent for more than 20 minutes; a finished or stopped subagent is never marked, a shell's row stays marked after it ended (its task notification is the authority). Stop a review subagent that has written nothing for 20 minutes and dispatch it again on a narrower scope; dispatch a subagent that the API's safety filter stopped again at once, with the same brief, on the fallback model. While waiting longer than a few minutes, tell the owner what is awaited and since when.
 

README.md

@@ -37,7 +37,7 @@ Until final acceptance begins, actual-editor development verification uses the o
 | How do development and review work?             | [Delivery](AGENTS.md#delivery)                                                                                    |
 | What is the current design authority?           | [Design target](PRODUCT_GOAL.md#design-target)                                                                    |
 
-Read [AGENTS.md](AGENTS.md) when starting or resuming work. Claude Code also enters through [CLAUDE.md](CLAUDE.md). PRODUCT_GOAL.md owns the outcomes, AGENTS.md the way of working, and the active cycle Issue the state.
+Read [AGENTS.md](AGENTS.md) when starting or resuming work; Codex loads it as its project instructions, and so does Claude Code while no `CLAUDE.md`, `.claude/CLAUDE.md` or `CLAUDE.local.md` overrides it. PRODUCT_GOAL.md owns the outcomes, AGENTS.md the way of working, and the active cycle Issue the state.
 
 ## Tracking and continuation