Mibayy/token-savior
🐍 🏠 🍎 🪟 🐧 - Structural code intelligence MCP server for AI-assisted development. Navigate and edit code by symbol names instead of raw text — symbol lookup, dependency graphs, call chains, dead code detection, and structural diff. Replaces grep/cat with semantic tools: 87% token reduction on large codebases.
Quick Install
{
"mcpServers": {
"mibayy-token-savior": {
"command": "npx",
"args": [
"-y",
"mibayy-token-savior"
]
}
}
}Using an AI coding agent (Claude Code, Cursor, etc.)? Copy a ready-made prompt that tells it to fetch the setup instructions and install this server for you.
Documentation Overview
Token Savior
One MCP server. One profile. 97.9% on tsbench at -80% tokens. Structural code navigation, persistent memory, and Bash output compaction for AI coding agents.
mibayy.github.io/token-savior -- project site + benchmark landing github.com/Mibayy/tsbench -- benchmark source + fixtures
Benchmark -- 96 real coding tasks (Claude Opus 4.7, May 2026)
| Plain Claude Code | With Token Savior | |
|---|---|---|
| Score | 141 / 180 (78.3%) | 188 / 192 (97.9%) |
| Active tokens / task | 17 221 | 3 395 (-80%) |
| Wall time / task | 110.6 s | 18.9 s (-83%) |
Reproduces with the optimized profile (single env var). See BENCHMARK-SUMMARY.
What's new
Release notes live where they can't drift out of sync with the code:
- CHANGELOG.md for the full history
- Releases for the tagged builds
- PyPI for what
pipwill actually give you
Quick start
pip install "token-savior-recall[mcp]"
Add to your MCP config (e.g. Claude Code):
{
"mcpServers": {
"token-savior-recall": {
"command": "/path/to/venv/bin/token-savior",
"env": {
"WORKSPACE_ROOTS": "/path/to/project1,/path/to/project2",
"TOKEN_SAVIOR_CLIENT": "claude-code",
"TOKEN_SAVIOR_PROFILE": "optimized"
}
}
}
}
That's it. TOKEN_SAVIOR_PROFILE=optimized ships the Pareto-optimum
config that wins tsbench. It bundles:
tiny_plus(15 hot tools manifest)- thin inputSchema (-44% manifest)
- capture sandbox disabled
- memory hooks gated for cross-project safety
No other tuning needed.
Activation (Bash compaction + rewriting)
Bash compaction and the PreToolUse rewriter are opt-in. Two env vars and one CLI call:
export TS_BASH_COMPACT=1 # PostToolUse output compactors (34 of them)
export TS_BASH_REWRITE=1 # PreToolUse command rewriter (10 rules)
ts init --agent claude --yes # auto-merge hooks into ~/.claude/settings.json
ts init is idempotent. It detects existing hook entries, dedups by
(matcher, command), prints a unified diff, and backs up settings.json
to .bak-YYYYMMDD-HHMMSS (UTC) before writing. Supported agents:
claude, cursor, gemini, codex, openclaw. Pass --dry-run to preview, or
--global to write the user-level config.
Optional audit log of every rewrite:
export TS_BASH_REWRITE_LOG=$HOME/.local/state/token-savior/rewrites.jsonl
Compactor catalog (34)
| Family | Compactors |
|---|---|
| git | status, diff, log, push/pull, commit, add, fetch, checkout, branch, worktree list, stash list |
| gh | run list, run view, pr diff, pr view, issue view, repo view |
| test/lint | pytest, jest, vitest, eslint, biome, cargo test, cargo build/clippy, tsc |
| cloud | kubectl get, kubectl logs, aws sts, aws ec2, aws lambda, aws logs, aws iam, aws dynamodb, aws s3 |
| docker | docker ps, docker logs |
| packaging | npm/yarn/pnpm list, pip list/show |
| shell catch-alls | grep, find, cat, curl |
Each compactor is a pure function (no I/O, no globals) returning a
token-efficient rendering. The dispatcher returns None when no matcher
fires, leaving the existing sandbox path untouched. Compound commands
(cd ... && cmd) fall through to the last meaningful segment.
ts_discover -- find missed TS opportunities
New MCP tool that scans your Claude Code transcripts for patterns where TS tools would have been cheaper than what the agent actually did.
ts_discover() # active project, last 30 days
ts_discover(project=None) # ALL transcript projects
ts_discover(format="adoption") # TS vs native ratio per session
ts_discover(format="adoption_json") # same, JSON
Findings: Read->Grep->Read chains, sequential find_symbol, edits
without get_edit_context, memory_search without memory_index,
native shell on code files. Args are pruned to load-bearing keys
(PII-safe). Streams JSONL with mtime fast-skip.
ts init CLI
ts init --agent claude [--global] [--dry-run] [--yes]
ts init --agent cursor
ts init --agent gemini
ts init --agent codex
ts init --agent openclaw
Detects the target agent's settings location, deep-merges the Token
Savior hook config (PostToolUse + PreToolUse), preserves existing
hooks, dedups, prints a unified diff. Backs up to
settings.json.bak-YYYYMMDD-HHMMSS (UTC). Re-running is a no-op.
What it does
Claude Code reads whole files to answer questions about three lines, and forgets everything the moment a session ends. Token Savior fixes both, plus a third axis: it now compacts the noisy Bash output that bloats turn budgets between code reads.
It indexes your codebase by symbol -- functions, classes, imports, call
graph -- so the model navigates by pointer instead of by cat. Measured
reduction: 97% fewer chars injected across 170+ real sessions.
On top of that sits a persistent memory engine. Every decision, bugfix, convention, guardrail and session rollup is stored in SQLite WAL + FTS5
- vector embeddings, ranked by Bayesian validity and ROI, and re-injected as a compact delta at the start of the next session.
And on top of that, since v4.1, sit the Bash compactors and the PreToolUse rewriter. Bench numbers above.
Profile comparison
| Profile | Tools exposed | Manifest tokens | When to use |
|---|---|---|---|
optimized | 15 | ~1.5 KT | Recommended default -- Pareto win on tsbench |
auto | adaptive | ~1-2 KT | Per-client telemetry-based (experimental) |
tiny | 6 | ~0.6 KT | Minimal hot loop |
lean | 51 | ~4 KT | Legacy -- broader surface |
compact-only | 1 | ~0.3 KT | Bash compaction only -- you already run symbol nav elsewhere |
full | 68 | ~6 KT | Everything exposed |
You probably want optimized.
How it composes with adjacent tools
Token Savior spans several layers, and most neighbouring tools occupy exactly one of them. Overlap is opt-out per layer, so running both is usually fine once you disable the half you already have. Thanks to @chirag127 for mapping this out in #45.
| Tool | Layer | Overlap | What to do |
|---|---|---|---|
| RTK | PostToolUse Bash output compression | Direct, with the 34 compactors | Pick one. TS_BASH_COMPACT=0 to defer to RTK |
| serena | Symbol-graph navigation | Direct, with find_symbol / get_dependents | Run TS as compact-only if serena is your navigator |
| codebase-memory | Persistent code graph | With the memory engine | TS_MEMORY_DISABLE=1 |
| Ponytail, Caveman | Output-side compression (code and prose) | Partial, output side only | Complementary, no knob needed |
The layers Token Savior owns that these do not: the PreToolUse Bash rewriter
(it shrinks the command before it runs, not the output after), structural
editing that keeps the index in sync, and the audit tools
(detect_breaking_changes, find_dead_code, analyze_config).
If you only want the Bash layer, TOKEN_SAVIOR_PROFILE=compact-only advertises
a single tool and leaves the compactors and rewriter running.
Token savings
| Operation | Plain Claude | Token Savior | Reduction |
|---|---|---|---|
find_symbol("send_message") | 41M chars (full read) | 67 chars | -99.9% |
get_function_source("compile") | grep + cat chain | 4.5K chars | direct |
get_change_impact("LLMClient") | impossible | 16K chars | new capability |
| 96-task tsbench (Opus, plain vs ts) | 17 221 active/task | 3 395 active/task | -80% |
| 7-day Bash output bench (v4.3) | ~30 K tokens/week | ~9.6 K tokens/week | ~20.4 K/week |
Install
pip (MCP server)
pip install "token-savior-recall[mcp]"
# Optional hybrid vector search:
pip install "token-savior-recall[mcp,memory-vector]"
uvx (no venv, no clone)
uvx token-savior-recall
Claude Code one-liner
claude mcp add token-savior -- /path/to/venv/bin/token-savior
Development
git clone https://github.com/Mibayy/token-savior
cd token-savior
python3 -m venv .venv
.venv/bin/pip install -e ".[mcp,dev]"
pytest tests/ -q
Suite size: 1898 passed, 2 skipped on main. CI green on Python 3.11 / 3.12 / 3.13.
Bench it yourself
The compactor numbers above come from replaying real Claude Code
transcripts through the dispatcher. Two scripts live under scripts/:
python3 scripts/bench_compactors_real.py # match rate + mean savings
python3 scripts/bench_compactors_unmatched.py # top unmatched commands
The first walks ~/.claude/projects/*/*.jsonl, replays every Bash
output through the registry, and reports per-family savings + overall
match rate. The second buckets the unmatched commands so the next
compactor target is obvious from the histogram.
To reproduce the tsbench score:
git clone https://github.com/Mibayy/tsbench && cd tsbench
python3 generate.py --seed 42
git tag v1
python3 breaking_changes.py
git tag v2
TS_PROFILE=tiny_plus TS_CAPTURE_DISABLED=1 python3 bench.py --tasks all --run B
Bonus: ts CLI for non-MCP agents
For agents without MCP (Cursor, Aider, Continue, scripts, CI), the ts
command exposes a subset of the tools via shell:
ts use /path/to/project
ts get my_function # JSON output
ts search 'pattern'
ts daemon start # ~145ms per call vs 1.5s cold fork
ts init --agent cursor # wire up Bash hooks for non-Claude agents
On Claude Code, prefer the MCP server -- measured cheaper than CLI on Opus 4.7. The CLI is there for the portability case.
Environment variables
All optional. Values shown as =1 also accept nothing else — set exactly 1;
values shown as bool accept 1/true/yes (and on where noted).
Server & tool manifest
| Var | Default | Purpose |
|---|---|---|
WORKSPACE_ROOTS | current dir | Comma-separated project roots to index. Codex trap: Codex whitelist-filters the MCP server environment, so an exported shell variable never arrives — set it in config.toml under [mcp_servers.token-savior] env (or env_vars) |
PROJECT_ROOT | — | Single-root alternative to WORKSPACE_ROOTS |
CLAUDE_PROJECT_ROOT | — | Deliberate active-project override (Token Savior's own contract — no host sets it). Registered if valid, wins over every other boot signal |
TS_STICKY_ACTIVE | off (bool, on ok) | Freeze the active project: explicit project= hints and absolute path arguments still route each call, but no call repoints the shared default. For parallel agents in sibling worktrees |
TOKEN_SAVIOR_PROFILE | full | Tool profile. optimized — the value the quickstart config and ts init recommend — ships the Pareto manifest, implies thin schemas, and omits the capture tools from the manifest |
TS_THIN_SCHEMAS=1 | off (on in optimized) | Strip verbose tool schemas from the manifest |
TS_AUTO_HOT_K | 10 | Hot-tool count exposed by the telemetry-driven auto profile |
TOKEN_SAVIOR_CHAIN_NUDGE | on | 0/false/off disables chained-tool nudges |
TS_MEMORY_DISABLE=1 | off | Disable the memory engine (clean-context workloads) |
TS_CAPTURE_DISABLED=1 | off | Skip read-side capture sandboxing and drop the capture tools from the manifest (no profile flips this; optimized only hides the capture tools) |
TS_CODE_MODE_DISABLE=1 | off | Disable code-mode tools |
TS_CODE_MODE_NODE | node | Node binary used by the code-mode sandbox |
TS_RESOURCES_DISABLED | off (bool) | Don't expose observations as ts://obs/{id} MCP resources |
TS_WARM_START | off (bool) | Pre-build project slots at startup |
TOKEN_SAVIOR_NO_WARMUP | off (bool) | Skip the ts_search embedding warm-up |
TS_SEARCH_COLD_DELEGATE | off (bool, on ok) | Delegate the cold ts_search call to a running ts daemon |
TS_SOCK | /tmp/ts.sock | Unix socket of the ts daemon (CLI + cold delegate) |
TOKEN_SAVIOR_CLIENT | auto-detected | Client label (claude-code, …) for telemetry/client detection |
TOKEN_SAVIOR_SESSION_LABEL | — | Free-form label attached to session telemetry |
Indexing
| Var | Default | Purpose |
|---|---|---|
INCLUDE_PATTERNS | built-in list | Colon-separated globs; replaces the default include list |
EXCLUDE_PATTERNS | built-in list | Colon-separated globs; replaces the default exclude list |
EXCLUDE_EXTRA | — | Colon-separated globs appended to the default excludes |
TOKEN_SAVIOR_EXCLUDE_PATTERNS | — | Colon-separated globs appended at the indexer level |
TOKEN_SAVIOR_MAX_FILE_SIZE | 500000 | Max file size (bytes) to index |
TOKEN_SAVIOR_MAX_FILES | 10000 | Max files per project |
TOKEN_SAVIOR_WATCHER | auto | File watcher: auto / on / off |
TS_WATCHER_FORCE_POLLING | off | Force the polling watcher backend |
Claude Code hooks
| Var | Default | Purpose |
|---|---|---|
TS_CAPTURE_THRESHOLD_BYTES | 4096 | Minimum tool-output size to sandbox |
TS_CAPTURE_REPLACE=1 | off | Strong-replace: tell the agent to ignore the inline output and capture_get the URI |
TS_CAPTURE_TTL_DAYS | 30 | Captures older than this are purged on the next capture_put; 0 disables the GC |
TS_BASH_COMPACT=1 | off | Enable PostToolUse Bash output compactors |
TS_COMPACT_INLINE_THRESHOLD | 4096 | Hybrid mode: compact-result size above which the full original is also sandboxed |
TS_COMPACT_TINY_THRESHOLD | 256 | Hybrid mode: compact-result size below which the sandbox is always skipped |
TS_BASH_REWRITE=1 | off | Enable the PreToolUse Bash command rewriter |
TS_BASH_REWRITE_LOG | — | JSONL audit log of every rewrite |
TS_HOOK_MINIMAL=1 | off | SessionStart memory hook emits only the Memory Index block |
Memory extras
| Var | Default | Purpose |
|---|---|---|
TS_VIEWER_PORT | off | Port for the observation web viewer (unset = disabled) |
TS_AUTO_EXTRACT=1 + TS_API_KEY | off | LLM auto-extraction of memory observations (Anthropic API key required) |
TS_MODEL | claude-sonnet-4-6 | Auto-extraction model override |
TOKEN_SAVIOR_MEMORY_AUTO_SAVE=1 | off | Auto-save memory observations |
TELEGRAM_BOT_TOKEN + TELEGRAM_CHAT_ID | — | Critical-observation feed |
Storage, dashboard, debugging
| Var | Default | Purpose |
|---|---|---|
TOKEN_SAVIOR_STATS_DIR | ~/.local/share/token-savior | Telemetry + stats directory |
TOKEN_SAVIOR_DASHBOARD_HOST | 127.0.0.1 | Dashboard bind host |
TOKEN_SAVIOR_DASHBOARD_PORT | 8921 | Dashboard port |
TOKEN_SAVIOR_INCLUDE_TMP_PROJECTS | off (bool) | Dashboard also lists projects under temp dirs |
TOKEN_SAVIOR_DEBUG=1 | off | Debug logging |
TOKEN_SAVIOR_TRACE | off (bool) | MCP request lifecycle tracing |
Not knobs: CLAUDECODE, CLAUDE_CODE_ENTRYPOINT, CLAUDE_PROJECT_DIR,
CLAUDE_CONTEXT_REMAINING_PCT, CODEX_* and HERMES_* are read for host/client
detection and boot-time project hints — the environment sets them, you don't.
(CLAUDE_PROJECT_DIR is what Claude Code actually exports; it always names the
main checkout, never the worktree the session works in, so the launch directory
outranks it when that directory is a linked worktree. CLAUDE_PROJECT_ROOT
moved up into the knobs table: nothing sets it but you.)
Naming trap: TS_PROFILE in the benchmark snippets is tsbench's variable;
the server reads TOKEN_SAVIOR_PROFILE.
License
MIT