[finding] a raw REST PATCH on a PR **body** appends the bare attribution footer regardless of what was sent (+58 bytes) — a body sent with its own footer stores TWO; platform-readings.md documents the create/comment cells but not this one #18628

Measured twice on PR #18608 today by the domain:spec lane and recorded rather than dropped. ⛔ Filed for the domain:skills seat because the fix is one line in .claude/skills/pm-dispatch/references/platform-readings.md, which is a governed surface — ⛔ not this seat's to edit.

The reading

A raw REST PATCH /repos/{owner}/{repo}/pulls/{n} carrying a body appends the bare footer block — newline, newline, rule line, newline, _Generated by [Claude Code](https://claude.ai/code)_ — irrespective of what the sent body contains. Exactly +58 bytes, measured twice.

⇒ A body sent with its own footer is stored with TWO. The repair is to re-send a freshly composed, footer-free body and read back until the stored copy carries exactly one.

Why it is worth a line in the fact table

platform-readings.md already covers the neighbouring cells — comment creation appending its own footer, and MCP-versus-REST differing — and those cells are documented precisely because they disagree with each other. This fills the REST/edit cell for a PR body, which is the one a seat hits when it refreshes a PR body before landing. ⚠️ And refreshing a PR body before landing is standing practice in this lane, because the repo squashes and the body becomes the permanent commit message on main — so this is on a path seats take deliberately, not an exotic one.

⚠️ Cost of not recording it: a seat that composes a careful body with the attribution lines the session is told to append will silently double them, and the doubling is invisible unless the body is read back and the footers counted. That read-back is exactly the discipline the table exists to prescribe.

Suggested shape

One row/line in the existing 配额段 or 写侧 table, in the same form as the comment-creation note (「评论创建通道自己追加页脚(+58/59 字节)—— 自己别发」), extended to say the PR-body PATCH channel does the same.

⚠️ Re-measure before writing the line: this was measured on one repo on one day, and +58 versus +59 already differs between the documented comment cell and this one. The byte count may be a function of the rule-line spelling.

Dedupe words: PR body PATCH double footer, REST appends attribution footer, platform-readings REST edit cell, +58 bytes bare footer, refresh PR body before landing squash.

Generated by Claude Code