Use this to discover vault structure before deeper reads. Return an offset/limit paginated list of notes in the vault, optionally scoped to a subfolder and/or filtered by tags or top-level frontmatter (for example, frontmatter={'confidence': 'needs_verification'}). Each entry includes the stable ULID, title, tags, aliases, and timestamps.

Fetch the full context behind a search hit before answering from a snippet alone. Fetch a single note by its ULID, indexed chunk_id, or vault-relative path. chunk_id inputs return format='chunk' with the sandbox-wrapped chunk body; a parent-hash mismatch returns an explicit stale-chunk error. Chunk reads ignore offset/limit. For note inputs, format='full' returns the sandbox-wrapped body and offset/limit page large notes by character range; format='map' returns the heading outline only (cheap to scan before requesting full content).

First stop for any question about the user's notes, projects, decisions, or past work - search before saying you do not know. Full-text BM25 search over the FTS5 index. Returns ranked sandbox-wrapped snippets with term highlighting. Requires datacron index to have been run first. By default, explicitly superseded notes are demoted; set include_superseded=true to inspect historical notes.

Regex search via ripgrep. Returns ranked sandbox-wrapped match lines with term highlighting, resolved to indexed chunks. Restrict file scope with glob (e.g. '*.md'). Requires rg on PATH and datacron index for chunk resolution.

Use this to find related context the user did not mention. Return chunks whose wikilinks point at the given target. Target may be a note ULID or a wikilink alias (resolved via title -> filename -> aliases). Empty list if unresolved or no incoming links.

Use this when indexed sections may conflict or refine one another. Scan mode returns deterministic section-level candidates and read-only proposal tokens; summary detail omits redundant alternative previews while full detail retains them for debugging. confirm mode validates one token and returns an exact existing write-tool call. This tool never writes, including after elicitation or confirmation.

Return truthful read-only health for index freshness, vault integrity, point-in-time checksum, durability capability, and invariant evidence.

Call this proactively when a durable fact, confirmed decision, or user preference emerges in conversation - do not wait to be asked. Skip speculation and one-off chatter. Write a new typed _memory Markdown note. Use rejected entries in 'option -- reason' format to record discarded options so a future agent does not propose them again. This is a write operation: it is confined to DATACRON_WRITE_PATHS, never overwrites existing files, writes a durable operation record, and relies on the MCP client's tool approval for human-in-the-loop review.

Use this when new information extends a topic that already has a note, instead of creating a duplicate. Append a Markdown entry under a heading in an existing memory note. This is a write operation: it is confined to DATACRON_WRITE_PATHS, stores content-addressed history, writes atomically, and relies on the MCP client's tool approval for human-in-the-loop review.

Use this when a fact's lifecycle changes: verified today, superseded by a newer note, or confidence raised or lowered. Prefer invalidating an outdated fact (invalid_at + invalidated_by) over deleting or rewriting it: history stays queryable. Use rejected entries in 'option -- reason' format to record discarded options so a future agent does not propose them again. Update frontmatter fields on an existing memory note. This write operation only changes origin, confidence, last_verified, supersedes, rejected, valid_from, invalid_at, invalidated_by, and the automatic updated timestamp; the Markdown body is preserved.

Use this to rewrite an outdated section in place when the topic already has a note. Replace the content under one existing Markdown heading. Pass the note's current content_hash as expected_hash for CAS. The operation preserves the heading line and non-target sections, stores exact prior history, and writes atomically.

Use this to undo a bad write by restoring exact prior bytes. Restore a note to exact content-addressed history bytes. Pass the current content_hash as expected_hash for CAS. The revert is itself durable, reversible, indexed, and operation-logged.

List committed operation metadata for one note without reading history content or modifying the journal.

Query committed operation metadata by time range, tool, or note. This read-only operation never changes the journal or vault.