Agent Booster
Cut AI coding agent token costs 5–15x by routing only the code that matters.
Instead of sending full source files to the model on every read, Agent Booster builds a symbol index of your codebase and returns only the functions and classes relevant to the current task.
How it works
Without Booster With Booster
───────────────── ────────────────────────────
Read executor.py smart_read executor.py + task
→ 1,881 lines (~6k tokens) → 3 matching functions (~200 tokens)
Five layers work together:
| Layer | What it does |
|---|
| Symbol index | tree-sitter parses every .py, .ts, .tsx, .js, .jsx file, extracts functions/classes into SQLite |
| Vector embeddings | sentence-transformers encodes each symbol for semantic search |
| Smart read | given a file + task, runs per-file vector search and returns only matching symbol line ranges |
| MCP server | exposes four tools over stdio — any MCP-compatible agent can call them |
| Platform init | one command writes the right config for Claude Code, Cursor, Windsurf, or Codex |
Installation
Requires Python 3.10+.
pip install agent-booster
pip install agent-booster[embed]
Quickstart
Step 1 — Wire up your AI tool
booster init claude
booster init cursor
booster init windsurf
booster init codex
booster init all
Each command shows exactly what files will change, asks for confirmation, then writes them. Fully reversible:
Example — wiring up OpenAI Codex (booster init codex → booster start → booster gain):
Run once per project, not once per session.
The hooks live in .claude/settings.json and .mcp.json at the project root.
Every Claude Code session opened in this directory — any terminal window, same machine — picks them up automatically.
No per-session setup needed.
Step 2 — Index your codebase
Run once from your project root. Re-run after large refactors.
booster index && booster embed
The index is stored at .booster/ (gitignored). The index is shared across all sessions.
Step 3 — Restart your AI tool
The agent-booster MCP server is now available in every session. Claude Code (and other tools) will use smart_read and search_context automatically on indexed files.
Step 4 — Track savings
CLI reference
Writes the MCP server config and rules file for the target platform. Asks for confirmation before making any changes.
booster init claude
booster init cursor
booster init windsurf
booster init codex
booster init all
booster init claude --yes
Cleanly undoes everything init wrote. No residue.
booster remove claude
booster remove cursor
booster remove windsurf
booster remove codex
booster remove all
booster index
Scans all .py, .ts, .tsx, .js, .jsx files from the current directory. Extracts functions, classes, methods, and interfaces into .booster/symbols.db. Skips node_modules, .venv, __pycache__, .git, .booster, .next, dist, build.
booster embed
Builds sentence-transformer vector embeddings for all indexed symbols. Required for semantic search_context calls. Uses all-MiniLM-L6-v2 (local, no data leaves your machine).
booster search "<query>"
Keyword search across all indexed symbols. Returns file path, line number, kind, name, and signature.
booster search "guard install"
booster route "<task>"
Recommends haiku, sonnet, or opus based on task complexity — keyword signals, file count, and symbol count.
booster route "fix the guard SSE role check"
booster route "refactor the entire runtime compiler and DSL layer"
booster serve
Starts the MCP server over stdio. Called automatically by Claude Code, Cursor, Windsurf, and Codex when configured via booster init. You rarely need to run this directly.
booster gain
Shows token savings from past smart_read calls — total reads, tokens served vs. tokens saved, savings rate, and top files by savings.
Agent Booster — Token Savings Report
─────────────────────────────────────
Active days: 3
Total reads: 47
Tokens served: 12,400
Tokens saved: 89,200
Savings rate: 88%
Top files by savings:
executor.py 18,400 tokens saved (12 reads)
guard.py 14,200 tokens saved (8 reads)
Once booster serve is running, these four tools are available to the agent:
get_symbols(file)
Returns all indexed symbols for a file — name, kind, line range, and signature. No file read required.
Input: { "file": "apps/api/app/runtime/executor.py" }
Output: function run_workflow (lines 42-89): def run_workflow(...)
class WorkflowState (lines 91-140): class WorkflowState:
search_context(task)
Semantic vector search across all symbols in the index. Returns top 10 matches by cosine similarity. Falls back to keyword search if embeddings haven't been built.
Input: { "task": "guard install uninstall" }
Output: apps/web/src/app/settings/modules/page.tsx:99 function handleInstall — function handleInstall() {
apps/web/src/components/guard/GuardNav.tsx:13 function GuardNav — function GuardNav() {
...
smart_read(file, task)
Runs per-file vector search and returns only the source lines for matching symbols, with a header showing name and line range. If no symbols match, returns an explicit message so the model knows to fall back to a full Read rather than silently receiving the whole file.
Input: { "file": "apps/api/app/runtime/executor.py", "task": "execute output block" }
Output: # function _execute_output (lines 1165-1210)
def _execute_output(block, state, credentials, ...):
...
route_model(task, files?)
Recommends haiku, sonnet, or opus based on task complexity signals. If files is omitted, auto-detects via search_context.
Input: { "task": "fix the login redirect bug" }
Output: { "model": "haiku", "reason": "narrow task — 1 symbol in 1 file" }
What booster init claude writes
| File | Change |
|---|
.mcp.json | Adds agent-booster to mcpServers |
CLAUDE.md | Appends booster usage rules block (sentinel markers) |
.claude/settings.json | Wires PreToolUse (Read + Grep) and UserPromptSubmit hooks |
.claude/hooks/booster-gate.py | Blocks Read on indexed files — forces smart_read |
.claude/hooks/booster-grep-nudge.py | Nudges semantic Grep patterns toward search_context |
.claude/hooks/booster-route.py | Auto route_model — recommends haiku/sonnet/opus on every user turn |
booster remove claude removes all six, cleanly. No residue.
Where it fits
Agent Booster is the third layer in a three-layer token reduction stack:
Layer 3 — Agent Booster AST+semantic routing, smart file reads
Layer 2 — RTK Token compression on CLI/git/build output
Layer 1 — Prompt caching Stable context reuse (native to Claude Code + API)
Each layer is independent and addable separately.
Common questions
Does it work if I open a second terminal?
Yes. The hooks are wired into .claude/settings.json and .mcp.json in your project root — not inside a specific terminal session. Any new Claude Code window you open in this project picks them up automatically.
Do I need to run booster init again after restarting my machine?
No. booster init writes files to disk once. They persist across restarts and across sessions. The only time you re-run it is if you delete those files or switch to a new project.
Do teammates need to run booster init too?
Yes — once per developer, once per project. If you commit .mcp.json and .claude/settings.json to the repo, teammates get the hooks when they clone. They still need to run pip install agent-booster[embed] and booster index && booster embed locally, since the symbol index is gitignored.
Can I undo it completely?
Yes. booster remove claude removes all six files and cleans the settings entries. No residue.
Claude Desktop
Add to ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\Claude\claude_desktop_config.json (Windows):
{
"mcpServers": {
"agent-booster": {
"command": "booster",
"args": ["serve"]
}
}
}
Run booster index && booster embed once from your project root before starting Claude Desktop. No env vars required.
Project layout
tools/booster/
├── README.md
├── pyproject.toml
└── booster/
├── cli.py # click commands: index, embed, search, serve, init, remove, route, gain
├── indexer.py # tree-sitter parser + SQLite symbol store + vector search
├── retriever.py # smart_read: per-file vector search → relevant line slice
├── mcp_server.py # MCP server: get_symbols, search_context, smart_read, route_model
└── stats.py # token savings tracking (booster gain)