Syncdocs: the code is the spec for every fact in the docs

Documentation carries two kinds of text: facts that the code can confirm or refute, and prose that only a person can judge. The idea this skill turns on is that every fact is re-read from the code before it is written, and nothing else is touched. A version comes from the manifest, a command from the scripts, a tree from ls, a feature from the file that implements it. Prose, tone and section order stay the author's, and a claim the code can neither confirm nor refute goes to the person, not into an edit.

Written by the engineer who maintains it, from the documentation passes they run on their own repositories; provenance.md has the record.

When to use

After a change to versions, dependencies, scripts, structure or features, when the docs may no longer match; before a release; or when asked to check whether the docs are accurate.

The user's words override the default: "do not commit", "I want to review the diff" or "just tell me" mean no commit, or no edit, exactly as asked. A repository named but not present is cloned from its public URL into a scratch directory; that clone and the package registry are not external services in an eval's sense. Leave a working directory that is not the target as it was, apart from a report file if asked.

When NOT to use

Architecture

discover docs --> README.md, CLAUDE.md, AGENTS.md, docs/** (only what exists)
      |
ground truth  --> manifest + lockfile, scripts/targets/CI, ls, the implementing file
      |
compare       --> each claim: accurate | stale (code says X) | unverifiable
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sync          --> targeted edits to stale facts, the same fact equal in every file
      |
report        --> changed / verified accurate / flagged
      |
commit        --> doc files only, "docs: sync documentation with codebase state"

The seam is the target repository itself: its manifests decide the versions, its scripts and targets decide the commands, its directories decide the tree, and its own commit convention and changelog owner stay with commit and bumpv. There is no adaptation.md; this paragraph stands in for it.

Critical facts

1. A declared range is not an installed version. "next": "^16.2.0" permits many releases; the lockfile says which one resolved. A doc that names an exact version takes the lockfile's; a doc that names a range or a major takes the manifest's (ground-truth.md).
2. A documented command is real only if the repository defines it. npm run lint with no lint script fails on the reader's first try; the script, target or CI step must exist before the line stays. A missing one is stale, never flagged: it takes the name of a script of the same purpose (lint to typecheck), or is removed from its sentence, and nothing is added in its place.
3. The docs' tree is a claim like any other. Directories move without anyone editing the README, so the structure section is rebuilt from ls and the tracked files, never from the doc's own tree.
4. Agent instruction files are executed, not read. CLAUDE.md and AGENTS.md tell agents what to run; a stale command there is run on every session, so those files are checked first and kept lean.
5. One fact, one value, in every file. A version or command that appears in several docs is synced in all of them in the same pass, or the disagreement is reported; a half-synced fact is a new stale fact.
6. A repository without a manifest still has ground truth. For a markdown-only repository the newest changelog section, the tracked files and the git tags are the facts; the changelog is read, never edited.

Hard rules

Ground truth comes from the code, never from the docs or from memory. Every value written is one you read in this session from a manifest, lockfile, script, target, CI file or ls.

Only facts change. Fix a stale fact in place with a targeted edit; never rewrite prose, reorder sections, restyle, or add sentences, commands, badges, sections or features.

Never create a doc that does not exist. Sync README.md, CLAUDE.md, AGENTS.md and docs/ only where they already are; offer a missing file in the report instead of writing it.

Never touch CHANGELOG.md. bumpv writes it from the commit history; the docs: commit is the record of the sync.

An unverifiable claim is flagged, never silently kept or deleted. A feature whose file, route or flag you cannot find, or a removal that needs a decision, goes in the report for the person to settle.

Nothing stale, no edit and no commit. Say the docs are accurate and stop; no cosmetic change is made to justify a commit.

Commit only doc files, only when the user has not asked to review first, and with no AI attribution. The message is docs: sync documentation with codebase state, with no Co-Authored-By: trailer naming any model or tool, no generated-by line and no session link; check git log -1 --format=%B after.

Quick start

1. List the docs that exist, leaving out agent folders such as .claude/ and vendored copies, and read each one whole: syncing.md, Discover.
2. Establish ground truth from the repository's own manifests, scripts, tree and implementing files: ground-truth.md.
3. Classify every factual claim as accurate, stale or unverifiable, then edit the stale ones in place, file by file: syncing.md.
4. Report changed, verified and flagged as the final message. Changed is one fact per line, never grouped, as file: old to new (source), every removal included; then commit the doc files or stop as the user asked: reporting.md.

Reference directory

Part of the Timerise Skills index, which lists the sibling skills.