Give coding agents the exact APIs, examples, and pitfalls from your docs and source — not another web search.
ImplCache is a local MCP server backed by SQLite. It indexes documentation, project trees, PDFs, mirrored sites, and Git repos, then returns a budgeted, cited implementation package so agents can write correct code without scanning the whole tree.
Return the smallest sufficient package of accurate, implementation-ready context for the current coding task.
Without ImplCache With ImplCache
───────────────── ──────────────
Agent greps / opens many files Agent gets exact symbols
Agent skims broad docs One project-local example
Agent searches the web Init order + constraints
Agent may pick an obsolete API Citations back to your corpus
Works with Cursor and other MCP clients. Optional Librarian browser UI manages sources, jobs, search, and health — no Node.js at runtime (UI is embedded in the binary).
| Sources | Library | Search Lab |
|---|---|---|
 |
 |
 |
This repo ships a ready-to-run package under dist/: Windows binaries, empty starter database, docs, and helper scripts.
cd dist
.\run-librarian.cmd
# open http://127.0.0.1:8080/Or point Cursor at the binary (use absolute paths):
{
"mcpServers": {
"implcache": {
"command": "D:/path/to/implcache-mcp/dist/implcache-mcp.exe",
"args": [
"-db", "D:/path/to/implcache-mcp/dist/implcache.db",
"-mode", "agent"
]
}
}
}Then ingest something you own:
cd dist
.\ingestcli.exe -db .\implcache.db -mode markdown -root my-docs -path "C:\path\to\docs"
.\ingestcli.exe -db .\implcache.db -mode project -root my-app -path "D:\work\my-app"Full end-user docs: dist/README.md · dist/docs/INSTALLATION.md
dist/implcache.dbis a sanitized empty schema DB (no vendor corpora). Pack regenerates it withpwsh ./scripts/pack-dist.ps1and never copies a developer database.
Primary tool: get_implementation_context
{
"task": "Add a custom command using RegisterCommand and AddMenuItem",
"language": "cpp",
"technology": "Example Plugin SDK",
"preferredRoots": ["example-control-app", "example-plugin-sdk"],
"maxContextTokens": 2500
}Typical response fields: requiredApis, relevantSymbols, sequence, examples, constraints, pitfalls, citations, coverage, contextFingerprint.
Staged depth (don’t dump the corpus):
get_implementation_contextfind_symbol→search_knowledgeget_documentonly when the package isn’t enough
Agent playbook: docs/AGENT_GUIDE.md · Tool reference: docs/TOOLS.md
| Capability | Notes |
|---|---|
| Local-first | SQLite on your machine; no cloud required |
| Cited packages | Budgeted answers with source URIs |
| Multi-source ingest | Markdown/docs, project trees, web mirrors, PDF Stage 1, Git repos |
| Symbol search | Go, C/C++/C#, Python, JS/TS, Java (heuristic extractors) |
| Librarian UI | Dashboard, Sources, Jobs, Library, Search Lab, Health |
| Modes | agent (retrieval) vs admin (ingest / delete / recipes) |
| Optional semantics | Sparse term similarity (-enable-semantic) — not embeddings |
Requirements: Go 1.25+, pure-Go SQLite (modernc.org/sqlite, no CGO).
go test ./...
go build -ldflags "-X main.version=$(git describe --tags --always 2>/dev/null || echo dev)" -o implcache-mcp .
go build -o ingestcli ./cmd/ingestcli
./implcache-mcp -db ./implcache.db -mode agent
./implcache-mcp -version# Admin / corpus maintenance (stdio)
./implcache-mcp -db ./implcache.db -mode admin
# Librarian UI + mutating REST on loopback
./implcache-mcp -db ./implcache.db -http :8080 \
-enable-librarian -enable-http-mutations -mode admin
# → http://127.0.0.1:8080/
# Read-only admin surface (tools visible; writes denied)
./implcache-mcp -db ./implcache.db -mode admin -readonly
# LAN / Jetson: bind for remote Cursor (requires trusted network)
./implcache-mcp -db ./implcache.db -http 0.0.0.0:8080 -allow-remote-http \
-enable-librarian -enable-http-mutations -mode admin
# Cursor ~/.cursor/mcp.json → "implCacheRemote": { "url": "http://<host>:8080/mcp" }Remote Jetson Orin NX walkthrough: docs/REMOTE.md. Optional workspace defaults via .implcache.yaml and -workspace /path/to/repo (or -project-root my-app). See docs/CONFIGURATION.md.
React UI sources: frontend/ → rebuild into embedui/dist (or run scripts/pack-dist.ps1).
Prefer the offline CLI for large trees:
./ingestcli -db ./implcache.db -mode markdown -root my-sdk-docs -path /path/to/docs
./ingestcli -db ./implcache.db -mode project -root my-app -path /path/to/src
./ingestcli -db ./implcache.db -mode url -root web-docs -url "https://docs.example.com/api.html"
./ingestcli -db ./implcache.db -mode pdf-ingest -root manuals -path /path/to/manual.pdf
./ingestcli -db ./implcache.db -mode repo-ingest -name sdk -root sdk-main \
-url https://github.com/org/sdk.git -ref main -acq managed_cloneOr use Librarian / admin MCP tools. Details: docs/INGEST.md.
Each corpus is a portable URI tree (project://{rootName}/…, git://…, pdf://…). Ambiguous queries return needsChoice + availableRoots — agents should not guess across product families.
| Doc | Audience |
|---|---|
| docs/USERS_MANUAL.md | Operators (install, ingest, Cursor, Librarian) |
| dist/README.md | Binary package index |
| docs/AGENT_GUIDE.md | How agents should call tools |
| docs/TOOLS.md | Full MCP tool reference |
| docs/API_V1.md | Librarian REST /api/v1 |
| docs/ARCHITECTURE.md | Design & retrieval pipeline |
| docs/OPERATIONS.md | Ops, security, eval |
- Schema and ranking can still change; pin or vendor if you need stability.
- Symbol extraction is heuristic; neural embeddings are deferred (optional sparse semantic only).
- Keep HTTP on loopback unless you deliberately expose it (
-allow-remote-http+ reverse proxy + HTTPS + Librarian tokens). - HTTP mutations stay off unless
-enable-http-mutations. - SQLite WAL: fine for readers; serialize writers.
- An incompatible DB is refused — delete and re-ingest (no automatic migrations).
MIT — Copyright (c) 2026 Adam G. Sweeney <agsweeney@gmail.com>.
See LICENSE, NOTICE, and third_party/.