wave agent-rules: restore base check and hand-back identifiers; attribution from the brief (improvise-uj4k, improvise-1o0y)

The move in b6d2c47 dropped two items from the old brief lists: the agent
checking its base against the named commit, and reporting branch, head SHA,
PR number and per-ticket changes. The attribution line now comes from the
brief, so the shared file stays agent-neutral and ours still open with
"Posted by Claude".

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VdfEGXA7aJ6ftMsCc9PJze

.agents/skills/wave/SKILL.md

@@ -43,7 +43,7 @@ nobody corrects. The brief adds only what varies per wave:
 
 1. **The expected base commit, by name.** Worktrees do not reliably branch from
    HEAD. One was created three merges behind and was only noticed because it
-   was told to check.
+   was told to check. The agent checks against it: `agent-rules.md` rule 1.
 2. **A reference baseline**, so "N passing" is checkable and a drop is
    visible: Rust test count, harness counts, node counts, **and the machine**.
    The same commit once measured `improvise-io`'s binary at 1.4s on one machine
@@ -52,8 +52,10 @@ nobody corrects. The brief adds only what varies per wave:
 3. **Its ground, and the ground that is not.** Name any orchestrator-only file
    it is exceptionally allowed to edit.
 4. **Its `BEADS_ACTOR` and its tickets.**
-5. **The commit trailers and PR footer**, spelled out. They carry this
-   session's URL, which is why `agent-rules.md` cannot hold them.
+5. **The attribution line, commit trailers and PR footer**, spelled out.
+   They name the agent (Claude's line opens `_Posted by Claude (<model>)…_`)
+   and this session's URL, which is why the shared `agent-rules.md` cannot
+   hold them.
 6. **An explicit ask for what the ticket did not predict.** `agent-rules.md`
    lists it in the hand-back. Say it in the brief anyway: it is consistently
    the most valuable part of a hand-back, and agents omit it unless asked.

.agents/skills/wave/agent-rules.md

@@ -12,30 +12,34 @@ not in a second copy.
 
 ## Base, branch, push
 
-1. **Branch from `gh/main`, never `main` or `origin/main`.** `git fetch gh &&
+1. **Verify your base against the commit your brief names, first.** Run
+   `git log --oneline -1` and compare. Worktrees do not reliably branch from
+   the orchestrator's HEAD: one was created three merges behind, and it was
+   only noticed because the agent was told to look.
+2. **Branch from `gh/main`, never `main` or `origin/main`.** `git fetch gh &&
    git checkout -b <branch> gh/main`. A worktree handed to you may already sit
    on unpushed commits. Why: `AGENTS.md`, "Shipping a wave" (the two remotes
    both spelled `main`, and the worktree-base vector).
-2. **Before opening a PR, check `git diff --numstat gh/main...<branch>`.** Do
+3. **Before opening a PR, check `git diff --numstat gh/main...<branch>`.** Do
    not use `gh pr view --json files`: that is the union of your commits' files,
    not the effective diff.
-3. **Push with an explicit refspec:** `git push gh HEAD:refs/heads/<branch>`. A
+4. **Push with an explicit refspec:** `git push gh HEAD:refs/heads/<branch>`. A
    branch cut from `gh/main` tracks `gh/main`, so a bare push targets `main` and
    is refused.
-4. **Before pushing a fix to an existing PR, check `gh pr view <n> --json
+5. **Before pushing a fix to an existing PR, check `gh pr view <n> --json
    state`.** GitHub deletes a merged PR's branch. A push to it then prints
    `* [new branch]` and lands nowhere. Why: `AGENTS.md`, "Shipping a wave".
-5. **The "Session Completion" block near the end of `AGENTS.md` does not apply
+6. **The "Session Completion" block near the end of `AGENTS.md` does not apply
    to you.** It says `git merge origin/main` and then a bare `git push`. On a
-   wave branch the first is the #145 trap and the second is refused (rule 3).
-   Rules 1–4 replace it. The block sits between bd's generated
+   wave branch the first is the #145 trap and the second is refused (rule 4).
+   Rules 1–5 replace it. The block sits between bd's generated
    `BEGIN/END BEADS INTEGRATION` markers, so it is not edited by hand
    (improvise-x1uk).
 
 ## Commit early: a worktree is not durable storage
 
 Commit a WIP as soon as your first test run is green, and again after every
-meaningful step. Push your branch (rule 3) once it is worth keeping. An agent
+meaningful step. Push your branch (rule 4) once it is worth keeping. An agent
 finished a whole ticket with every gate green and lost all of it, uncommitted,
 when its worktree was deleted in a disk cleanup. A local commit survives a
 deleted worktree. Tidying history before the PR is fine; losing it is not.
@@ -148,10 +152,11 @@ text for any of these in your hand-back.
 - `gh` is shell-aliased to a different tool. Use
   `nix shell nixpkgs#gh --command gh …`, and pass bodies with `-F body=@file`.
 - **Everything posted goes out under the repository owner's account.** Open
-  every PR body and comment with:
-  `_Posted by Claude (<model>), an agent in Edward Langley's session._`
-- Commit trailers and the PR footer are given by your brief, verbatim. They
-  carry a session URL, so they cannot live here.
+  every PR body and comment with the attribution line your brief gives you,
+  verbatim. It names your agent and model, which is how our posts are told
+  apart from an automated Codex review (`AGENTS.md`, "Shipping a wave").
+- The attribution line, commit trailers and PR footer all come from your brief.
+  They name the agent and the session, so this shared file cannot hold them.
 - Read reviews with `./scripts/pr-reviews <n>`, and do not pipe it. How to tell
   a ChatGPT Codex review from ours, and why Copilot is not coming: `AGENTS.md`,
   "Shipping a wave". Answer each Codex review on its thread.
@@ -162,6 +167,8 @@ text for any of these in your hand-back.
 
 Report:
 
+- your branch, head SHA and PR number. Review is dispatched against the SHA;
+- what changed, per ticket;
 - the claim result;
 - your measured baseline;
 - whether the ticket reproduced (the SHA if it did not);