Regex search across every project under the root (code, then config/docs/SQL), each code hit tagged with the function it sits in. When the service or file is known, narrow with services/file. Paged, never silently cut: the header says COMPLETE or gives a cursor. Default view: every matching line; view: "summary" groups them by function and says it does not show every line. Long lines end with ….

Before writing new logic: find existing functions by describing the behaviour in words ("calculate order fee"). Lexical ranking over name, aliases, class, signature, doc comment, path, called names and body, with stem, abbreviation and synonym matching; each candidate says why it matched, and matches only via calls or body rank lower. Not semantic: if nothing fits, use spec_nav_similar_functions. Returns ids for spec_nav_read_function. Paged by limit/cursor.

Find functions that behave like a given one, whatever they are named, by comparing the calls they make and their body vocabulary. Subject: id, file+name, or code (a draft). Use on a draft before adding code, on a candidate to find siblings, or before changing logic that may be copied elsewhere. Ranked candidates list the calls and words they share. Similar is not interchangeable: read both.

Function catalog of a file, directory or service without bodies: qualified name, kind, signature, line range, export status, doc summary and id. Filter by services, file, name, kind, language. Paged; a coverage line names the files not read (syntax errors, unsupported languages, skipped), and the catalog is complete only when it says so. Inline anonymous callbacks are counted, not listed.

Read functions in full (signature, doc comment, imports used, source with line numbers), up to 10 per call with functions. For code you will not edit; to edit a file, Read it (Edit requires that). Identify by id, or file+name (+line). For a long function or lines outside any function, pass lines to get only ±around lines. Long functions come in parts with a cursor; nothing is cut silently. Answers STALE if the code changed since the id was issued. Does not say whether another service may import it.

The projects under the root as services values, with file and function counts and a coverage summary. Use when unsure of service names or whether SPEC_NAV_ROOT is right; not needed otherwise.

Call sites of a function or method across the repo, before changing its signature or behaviour. Narrow with "Class.method", className or file. TS/JS (and Vue/Svelte/Astro) are resolved with the type checker, so same-named methods on other classes are excluded; other languages are bound by evidence and each site's reason says which. likely, ambiguous, unresolved and dynamic sites are listed apart and are not confirmed callers. exhaustive is true only when type-checked targets have nothing left open; names computed at runtime, HTTP/RPC/queue calls and code outside the repo are never counted. Paged: partial names what is not shown yet.

Trace a flow across services, statically from source: HTTP client → route → handler, RPC call → handler, event/topic → consumers, plus direct calls inside each service. Use when a change touches an endpoint, RPC call or event. Start from a function (id or file+name), an endpoint or a topic; no start lists every link found. Each step has evidence, a confidence and a status (resolved, partial, ambiguous, unresolved, unmatched); partial, ambiguous and unresolved links are leads to check, and stacks without an adapter are reported as not traced.