ContextSliver

On-demand context management for AI coding agents. Stop reading whole files — ask for the connected subgraph instead.

<p align="center"> <img src="assets/hero-banner.jpg" alt="ContextSliver — from chaos to clarity: on-demand code context for AI agents" width="800"> </p>

The problem

When you ask an AI coding agent (Claude Code, Cursor, Cline) to "fix the bug in AuthService," it repeatedly reads entire files to find the 5% that's relevant — burning 40,000–80,000 tokens on a question that needed ~3,000.

find . -name "*.ts"   → 2,000 tokens (a file listing)
cat AuthService.ts    → 3,000 tokens (whole file)
grep -r "AuthService" → 5,000 tokens (40 matches)
cat AuthMiddleware.ts → 2,500 tokens (whole file, again)
... × 10 more ...

Existing tools don't fully fix it: Graphify dumps one enormous whole-repo map into context up front; Repomix packs the entire repo into one file; Aider's repo-map sends a whole-repo summary with every message. None of them track what the agent has already seen this session.

What ContextSliver does

ContextSliver runs as a background MCP server on your machine. It indexes your codebase into a local SQLite graph of every function, class, and import. When the agent needs context, it calls an MCP tool instead of reading files:

Agent:   "What connects to AuthService? Budget: 2,000 tokens."

ContextSliver:
  symbol:        AuthService  (src/auth/AuthService.ts)
  callers:       [AuthMiddleware, LoginController]      ← who uses it
  dependencies:  [UserRepository, TokenService]         ← what it uses
  already_in_context: [UserRepository]                  ← skipped, agent already has it
  // ~380 tokens

Three things make it different:

1. On-demand pruning — never sends the whole graph, only the connected subgraph for the task.
2. Session ledger — tracks what the agent has already seen and skips re-sending it.
3. One-command setup — npx contextsliver init. No database server, no API key.

Quickstart

# In your project root:
npx contextsliver init      # creates .sliver/, .mcp.json, CLAUDE.md, indexes the repo
npx contextsliver start     # runs the MCP server + file watcher (stdio)

Then restart Claude Code / Cursor / Cline — they'll pick up the five tools automatically. See the templates for client-specific config.

The five MCP tools

Tool	What it does	Typical tokens
cs_index_repo	Trigger a full re-index	~50
cs_get_context	Symbol definition + immediate connections	~300–800
cs_blast_radius	All callers + dependents up to N hops	~500–2,000
cs_search_symbols	Full-text search across indexed symbols	~200–600
cs_index_status	Index health, file count, last-updated	~100

Pass the session_id from your first cs_get_context call to every subsequent call to enable deduplication.

Supported languages

• TypeScript / JavaScript / TSX (v0.1)
• Python (v0.1)
• Go, Rust, Java — planned (see roadmap)

Adding a language = add a grammar package + a grammars/<lang>/tags.scm query + a fixture. See CONTRIBUTING.md.

How it works

Your codebase  ──chokidar──▶  Parser (Tree-sitter)  ──▶  SQLite graph (.sliver/index.db)
                                                                    │
                              MCP server (stdio) ◀──────────────────┘
                                    │   session ledger (.sliver/sessions.db)
                                    ▼
                          Claude Code / Cursor / Cline

• Parser: Tree-sitter extracts symbols + imports per file.
• Graph engine: stores symbol→symbol edges; bidirectional BFS (blastRadius) for blast radius with cycle detection.
• Session manager: per-session ledger computes deltas so already-sent context is skipped.
• MCP server: exposes the five tools over stdio.

Token counting

Counts use gpt-tokenizer (cl100k_base) and are labeled ~approximate — close enough for budget guidance, not billing.

Development

npm install
npm test            # unit + integration tests
npm run test:bench  # indexing benchmarks
npm run build       # tsc → dist/
npm run lint        # eslint

Requires Node ≥ 20.

Roadmap

• v0.1 ✅ TS/JS + Python, SQLite graph, session ledger, 5 tools, CLI, watcher
• v0.2 — incremental indexing polish, Cursor integration, CI benchmarks
• v0.3 — Go + Rust, monorepo workspace resolution, language-plugin docs
• v0.4 — PreToolUse hook, Java, published token-reduction benchmarks
• v0.5 — Streamable HTTP transport, DuckDB backend for 50k-file repos, PageRank ranking
• v1.0 — frozen API, optional native (napi-rs) engine, SCIP/LSP precision backend

See contextsliver-spec.md for the full specification.

License

MIT © Muneeb Ur Rehman