Synthesize Init

/synthesize-init

Install, update, or remove one managed route. Never create a directive file.

Consent

Approval is per target, operation, and exact bytes. Before writing, show the target, INSTALL, UPDATE, or REMOVE, and the exact diff. Record the current byte hash and the proposed replacement byte hash. Approval binds to all four: target, operation, current bytes/hash, and replacement bytes/hash. One approval may cover the displayed set. Any change to that set requires new approval.

Discover and classify

1. Resolve each runtime. For every possible target, verify synthesize is installed or otherwise resolvable by that runtime. A roster in one runtime proves nothing about another. Exclude unresolved runtimes and state why. If none resolve, stop with the relevant installation route.
2. Discover targets. Consider only existing standing directive files that the runtime documents or the user names. A project-scoped request excludes global files. List eligible files and ask which to touch. No eligible file means stop.
3. Classify exact current bytes. Ignore markers inside fenced code. Marker lines must contain only the exact marker.
   • MANAGED: exactly one begin marker and one later end marker, with no nesting. The bytes between them may be current or stale.
   • COMPATIBLE: no markers and a semantic equivalent that requires substantive output to load and follow /synthesize, keeps simple answers plain, and on a missing skill preserves meaning, leads with the bottom line, and states material uncertainty.
   • PARTIAL: no markers and a narrower, non-conflicting rule that provides only part of that behavior. Name the missing behavior.
   • UNMANAGED: no markers and no related rule.
   • CONFLICT: no markers and a rule whose required behavior conflicts with the managed block. Name the conflict; do not hide it as a partial rule.
   • MALFORMED: any other marker state, including duplicates, reversal, or nesting.

Operation matrix

An install or update is valid only in the states allowed above. Removal is a mutation only for MANAGED; removal from an unmanaged, partial, or compatible file is an explicit no-op. Never delete text merely because it resembles the route.

Safe replacement

For every mutating matrix cell:

1. Build the complete replacement bytes and show the exact diff. Bind approval as described above.
2. Immediately before writing, inspect the target and every parent component without following links. Stop on a symlink, junction, mount, or equivalent redirect. Require the current bytes and hash to equal the approved preimage.
3. Create a uniquely named backup with exclusive create semantics; never reuse or overwrite a path. Copy the approved preimage and verify its byte hash.
4. In the target directory, create a uniquely named staging file with exclusive create semantics. Write the full replacement, flush it, reopen it, and verify its byte hash equals the approved replacement hash.
5. Recheck target and parent metadata plus the target preimage. Use only a documented same-filesystem primitive that atomically replaces the target with the verified staging file. If the runtime or filesystem cannot provide that guarantee, stop before replacement.
6. Reopen the target and require exact replacement bytes and hash. Report the operation, backup, staging disposition, and verification.

On failure, preserve backups. Remove only a staging file created exclusively by this invocation, and only after its identity and expected bytes are rechecked; never clean another process's artifact. Earlier successful files remain as written. Report every target as changed, unchanged, or failed so mixed state is explicit.

Removing the managed block through this same procedure is the normal undo. Restoring an entire backup is a separate replacement: first compare backup, current, and proposed bytes, show the exact diff and hashes, and obtain fresh approval. A restore never overwrites edits made after the backup silently.

Managed block

Insert this verbatim:

<!-- synthesize-init:begin -->
Before composing substantive reader-facing output, load and follow `/synthesize`. Simple answers remain plain. If unavailable, preserve meaning, lead with the bottom line, and state material uncertainty.
<!-- synthesize-init:end -->

Only approved managed-block bytes may change inside the directive file. Named backup and same-directory staging artifacts are permitted solely for safe replacement. Do not reorder or edit other directive content.

This skill installs routing only. It does not run proactively or enforce that future agents obey the route.