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+# Instructions for the Labyricorn development log
+
+These instructions apply to `.labyricorn/devlog/` and help coding assistants
+maintain the project's public development narrative safely.
+
+## Format and ownership
+
+- Keep the devlog index at `devlog/contents.lr` using `_model: devlog` and
+  `schema_version: 1`.
+- Store each entry at `devlog/<stable-slug>/contents.lr` using
+  `_model: devlog-entry` and `schema_version: 1`.
+- Use lowercase hyphenated entry slugs. Published slugs are durable public URLs;
+  do not rename or delete them without explicit approval and a redirect or
+  archival decision.
+- Every entry must contain `title`, `date`, `author`, `summary`, `tags`,
+  `source_commit`, and Markdown `body` fields.
+- Keep entry attachments in that entry's directory. Only PNG, JPEG, and WebP
+  images are accepted by the Labyricorn importer.
+- Do not add templates, models, plugins, executable code, builds, application
+  state, credentials, or active third-party content below this directory.
+
+## Content guidance
+
+- Base entries on verifiable repository history, project documentation, and
+  implemented behavior. Do not invent motivations, results, release status,
+  user feedback, or completion claims.
+- Explain the milestone, why it mattered, and what changed. Keep one main
+  milestone per entry and write a summary that works in a chronological list.
+  Do not merely expand a commit message or enumerate every changed file.
+- Distinguish design and schema contracts from completed runtime behavior.
+- Link to the relevant canonical commit using the repository's HTTPS web URL.
+- Use the referenced commit's actual `YYYY-MM-DD` calendar date for retrospective
+  entries, not the date on which the prose was drafted.
+- Set `source_commit` to the full lowercase 40-character commit ID most directly
+  associated with the milestone. It must be an ancestor of the published branch.
+- Topics are comma-separated display labels. Unknown topics are allowed: the
+  site keeps them visible but unlinked. Do not create or edit the site's tracked
+  tag registry from this project repository.
+- Use Markdown without raw HTML, scripts, embedded credentials, or active
+  external content.
+- Multiple entries may share a date. The site resolves ties from source history;
+  do not invent timestamps or manual next/previous links.
+- Do not rewrite older entries merely because the implementation later changed.
+  Add a new entry or a clearly labelled correction when historical context is
+  needed.
+
+## Safety and review
+
+- Preserve unrelated project files and uncommitted work. The devlog owns only
+  `.labyricorn/devlog/`.
+- Do not commit or push unless the user explicitly requests publication.
+- Before publication, verify claims against the referenced commit, validate all
+  records, check that the source-commit link uses the same full commit ID, review
+  the exact devlog diff, and confirm unrelated files are not staged in the
+  publishing commit.
+- Prefer the repository-root `devlog_editor.py` for routine validation and safe
+  publication when it is available.