splinter

name	splinter
description	Use the splinter MCP tools instead of Read/Grep to explore code. Fn-level index — open_source for a function map, read_body for one function, search_bodies to grep, read_splinter/write_splinter for durable per-file memory. Edit the source file normally; the watcher re-splits.

splinter

Fn-level code index over MCP. Each source file is split into per-function .fs bodies under .splinter/, and gets a *.splinter.md note for durable memory. Source is truth; .splinter/ is a derived cache a one-way watcher rebuilds. Edit the source with normal tools — never the .fs files.

Navigate before reading

For indexed source, use the index first; open the raw file only if you still need it after:

1. search_bodies(query) / open_source(path) — locate the function.
2. read_splinter(path) — check prior notes.
3. read_body(path) — load just that function.
4. Read/Grep the whole source file only when steps 1–3 are not enough.

Tools

• index_dir(src_dir) — bootstrap: split a whole tree, every installed language at once. Run once if .splinter/ is empty.
• open_source(source_path) — function list with signatures, by size (⚠ over SPLINTER_MAX_LOC) + the file's splinter note.
• read_body(path) — one function body (.fs path; index-relative works). First line is §head <src>:<start>-<end> <name>. Rejects source files — use open_source.
• search_bodies(query) — grep across every indexed function; each hit maps back to source:line [fn].
• search_names(query) — regex over fn names + source paths only; returns paths, token-cheap.
• grep_files(query) — ripgrep raw source under a root; finds matches even in unindexed files.
• grep_source(query) — unified search across skeletons and bodies (scope: all | skel | body).
• ref_graph(path) — call graph for a fn name or .fs body: callers (in) and callees (out). An ambiguous bare name lists the qualified candidates instead.
• outline(path) — symbol map of a body/skeleton: fns, impls, structs, enums, traits, modules.
• list_bodies(dir) — functions in a dir, by size.
• find_large() — functions over SPLINTER_MAX_LOC.
• read_splinter(source_path) / write_splinter(source_path, content, append) — per-file memory.
• split(source_path) / dry_run_split(source_path) — split one file / preview its chunk boundaries.
• diff_body(path) — diff a body against the function's current region in the source.
• body_stats(path) — loc, bytes, refs in, mtime, origin source for one body.
• validate(fix) — index integrity check; fix=true purges orphans, dead refs, stale entries.
• list_languages() — installed extensions (17 languages out of the box via embedded tree-sitter, grammars auto-download; drop a grammar wasm + .scm query for more).

Use instead of

• Read file → open_source, then read_body for the parts you need.
• Grep → search_bodies.
• "who calls this / what does it call" → ref_graph instead of grepping the name by hand.
• Editing → read_body for the §head source line range, then Edit/Write the source file; the watcher re-splits.
• Anything you learn about a file → write_splinter. Check read_splinter before exploring.

Config (env vars or splinter.ini)

SPLINTER_SRC_DIR=src · SPLINTER_EXT (unset = every installed language; set a comma-separated list to restrict) · SPLINTER_MAX_LOC=256 · SPLINTER_DEBOUNCE_MS=500