Skip to main content
Glama
JSungMin

vs-token-safer

vs-token-safer · gamedev-log-analyzer

English · 한국어

Claude Code MCP release License: MIT PRs Welcome Stars

Search and edit a large Unreal C++ / Visual Studio / .NET codebase through an official language server's index (clangd / Roslyn / tsserver / pyright) instead of grep — token-capped to file:line, never source bodies. Plus a sibling plugin that reads tens-of-MB editor logs without dumping them into the conversation. Both cost ~99% fewer tokens than the naive approach. Local-only. No IDE required.

# Claude tries to grep code → the hook REWRITES it to the indexed query, in place:
$ grep -rn "SpawnActor" Source/**/*.cpp
↻ [vs-token-safer] Rerouted → search_symbol "SpawnActor"      # semantic, not a text match
  func SpawnActor (in AGameMode)   @ Source/GameMode.cpp:142   (+2 more)
  → ~120 tokens   (grep would have dumped thousands of lines)

# Editing that symbol? Name it — no Read-the-whole-file, no line counting:
$ replace_symbol_body symbol="SpawnActor" body="…"           # preview; apply=true writes
  replace_symbol_body "SpawnActor" — PREVIEW at Source/GameMode.cpp:142-160

Illustrative output with public Unreal Engine symbols. VTS_REWRITE=0 blocks instead of rewriting.

Why

  • grep on a giant Unreal C++ / .NET repo floods the context. The clangd/Roslyn index stays token-capped — ~97–99% smaller (benchmarks).

  • Claude keeps reaching for grep. The hook doesn't just block it — it rewrites the command to the indexed query in place, so the search still runs and the flow never breaks.

  • Edit by symbol, not by line. Replace/insert-around/delete a declaration by naming it — the index supplies the span, so you skip reading the whole file into context.

  • You can't tell how much grep still slips through. vts discover reads your recent sessions and reports exactly which searches bypassed the index and what they cost.

  • The language server runs headlessly — no editor open, unlike an IDE-proxy approach.

Related MCP server: codeix

Quickstart

# 1) Install (also auto-installs the gamedev-log-analyzer sibling)
/plugin marketplace add JSungMin/vs-token-safer
/plugin install vs-token-safer@vs-token-safer
/reload-plugins        # first run auto-installs the server deps (no manual npm)

# 2) Configure — detects the backend, asks for the project path, writes the config
/vs-token-safer:setup

Then restart the Claude Code session (the vs-search MCP server only starts on a fresh session). Verify the tools appear and that grep src/**/*.cpp is rerouted to the index. Prerequisites: Node ≥ 18 and a language server — clangd (C/C++) / Roslyn (C#) you install; JS/TS + Python auto-install. Details in Prerequisites below.

Want only the log analyzer? /plugin install gamedev-log-analyzer@vs-token-safer.

Tools

All search/edit goes through an official language-server index — clangd (C/C++), Roslyn (C#/.NET), tsserver (JS/TS), pyright (Python) — and comes back as a compact, capped file:line list (never source bodies). MCP server vs-search; same tools as the vts CLI.

Search / navigate

Tool

CLI

Does

search_symbol

vts symbol

Find a symbol declaration by name/substring (semantic, not text).

find_references

vts references

Every call site of a symbol. Takes the name directly (symbol="FooBar") — the one to reach for when you change a function/type and must touch every use.

goto_definition

vts definition

Definition of the symbol at a position.

hover

vts hover

Type/signature at a position.

document_symbols

vts symbols

Outline a file (classes/functions/types as file:line).

find_files

vts files

Find files by name/glob — token-capped stand-in for find -name.

search_text

vts text

Raw text/regex search — capped stand-in for grep (path=/glob=/docs=true to target).

Edit (symbol-level — name it, don't line-count) — preview by default, apply=true writes.

Tool

CLI

Does

rename

vts rename

Semantic project-wide rename (every reference, not a text sed).

replace_symbol_body

vts replace-symbol

Replace a whole declaration (signature + body) by name — the index supplies the span.

insert_after_symbol

vts insert-after

Insert text after a declaration (e.g. add a sibling method).

insert_before_symbol

vts insert-before

Insert text before a declaration (e.g. an import/attribute).

safe_delete

vts safe-delete

Delete a declaration — refuses while it's still referenced unless force=true.

Version control (output compaction, read-only)

Tool

CLI

Does

vts_git

vts git

Run a read-only git status/log/diff and group/dedup/cap the output. Mutating subcommands refused.

vts_p4

vts p4

Same for Perforce opened/status/changes/reconcile.

Plus vts_warmup, vts_setup, vts_config, vts_savings, vts_savings_reset, vts_discover, vts_gen_compile_db. Or hand a whole "where is X / what calls Y / find file W" lookup to the code-locator subagent — it searches in its own context and returns only the file:line table.

$ vts symbol --q SpawnActor --projectPath ./MyGame
3 symbol(s) matching "SpawnActor" (backend: clangd, root: ./MyGame):
func SpawnActor (in AGameMode)  @ MyGame/Source/GameMode.cpp:142
method SpawnActorDeferred (in UWorld)  @ MyGame/Source/World.cpp:88
func SpawnActorFromClass  @ MyGame/Source/SpawnLib.cpp:31

✓ Saved ~4,200 tokens here (96.8% / 31× smaller than the raw index response).

How it works

clangd and Roslyn already do the semantic analysis. What this plugin adds is enforcement, a token cap, and a headless spawn + warm-up, so Claude actually uses the index instead of grep:

Layer

Effect

Rewrite/enforcement hook

Covers four surfaces. Bash grep/rg/find -name over source → rewritten to the equivalent vts query in place (identifier → search_symbol, literal → search_text, find <dir> -namefind_files rooted at <dir>); ambiguous cases (pipeline, multi--name) block. Grep tool symbol hunt (bare identifier, ::/(/void·class regex, or a FooBar|BazQux CamelCase alternation) → blocked with a ready-to-use call; freeform/keyword alternations stay a warn. Glob tool concrete code file (*.cpp, Foo.h) → blocked toward find_files. Edit/MultiEdit that replaces or adds a whole declaration → a model-visible nudge toward the symbol-edit tools (replace_symbol_body/insert_after_symbol), escalating to a block on a safe insert after repeated ignores (VTS_EDIT_WARN, VTS_EDIT_BLOCK_AFTER); a sub-declaration tweak stays silent. Messages are agent-directed and i18n'd (EN/KO). Logs/.md/config pass through. Knobs: VTS_REWRITE=0, VTS_GREP_BLOCK=0, VTS_ENFORCE=0.

Token-capping core

Turns LSP results into kind name @ file:line, caps, appends … N more. A refs-heavy result collapses to one row per file (Foo.cpp:42,88,120) with a shared dir prefix factored out once (VTS_COMPACT_RESULTS=0 restores per-line). A truncated find_files/search_text tees the full set to a recovery file.

Symbol-level editing

replace_symbol_body/insert_*/safe_delete resolve a declaration by name via the outline and splice text at its exact span — preview by default, apply=true writes, safe_delete refuses while referenced. No whole-file Read into context.

Headless LSP client

A fully-owned LSP client spawns the official engine over stdio. The project root is resolved per call (explicit projectPath → the file's enclosing project → the MCP workspace root), so one global server answers for every repo a session touches. Live backends are pooled and bounded (VTS_MAX_BACKENDS + idle reaper).

Savings + discover

A local ledger records every search's tokens-saved (vts savings, with a 30-day graph). vts discover scans recent sessions for searches that bypassed the index — so you see the catch-rate, not just the wins.

Engine = official, glue = ours. clangd (LLVM) and Roslyn (Microsoft) do the analysis; this repo only writes the LSP↔MCP glue. No third-party MCP server runs over your source. Local-only, nothing uploaded.

The two plugins

Plugin

Does

Needs

vs-token-safer (this page)

Force code search/edit through the clangd/Roslyn/tsserver/pyright index over Bash grep, token-capped to file:line

Node + a language server (clangd / Roslyn you install; JS/TS + Python auto). No IDE.

gamedev-log-analyzer

Parse/dedup/classify huge Unreal/Unity/Godot/MSVC-UBT logs, search + diff + extract scalars

Node only

vs-token-safer declares gamedev-log-analyzer as a dependency, so one install pulls in both. Used together: the log analyzer emits file:line per entry → hand it to goto_definition/find_references to open the code, without grepping or dumping the raw log. The handoff runs in reverse too — a code search aimed at a log (Logs/, .log/.jsonl) points you back at gamedev-log instead of an empty result.

Combined savings (measured)

Bash / raw

Plugin

Reduction

Symbol search on a real UE5 repo (FGameplayTag)

~282,194 tok

~2,048 tok

~99.3% (~138×)

Raw index response → capped list (eval, 1,000 symbols)

~57,308 tok

~1,549 tok

~97.3%

Read a ~1 MB editor log (summary)

~267,000 tok

~130 tok

~99.95%

Performance

A real A/B on a large Unreal Engine 5 project: finding one public engine symbol (FGameplayTag) via Bash grep-and-paste vs this plugin. No project source is reproduced, only aggregate counts; see BENCHMARK.md.

Bash grep-and-paste (whole repo)

Plugin (clangd index, capped)

What the model receives

5,654 lines / 1,010 files

47 semantic decls (file:line)

Tokens to the model

~282,194

~2,048

~99.3% fewer (~138×). grep returns the full text of every matching line and matches by text (comments, strings, unrelated identifiers); the plugin returns one file:line per semantic hit, capped. The mock-LSP eval (node eval/run.mjs, no toolchain) gates this on every commit: ~57,308 → ~1,549 tok = 97.3% (53/53 checks).

  • Recall: the plugin returns the top N (cap), not every textual occurrence — the withheld tail is mostly comments/includes/substring noise. Need exhaustive? Raise maxResults, or use grep.

  • Precision: grep matches every substring (Foo also hits FooBar); the index returns distinct semantic declarations.

So for navigation (a definition plus representative usages) the plugin is both more accurate and far cheaper. For an exhaustive occurrence audit, raise the cap or fall back to grep on purpose.

clangd indexes asynchronously, so the first search pays a one-time warm-up. vts handles this like an IDE: the MCP server pre-warms at boot (VTS_PREWARM, on when projectPath is set) and keeps the client cached for the session, so you pay it once. vts warmup builds the on-disk index up front (CLI/CI), and VTS_CLANGD_REMOTE points clangd at a shared prebuilt index server.

Ordering matters: clangd boosts the priority of files you open, so vts warms query-history-first, then what you're editing now (git status / p4 opened), then git-log recency, then include-centrality, then mtime. On a huge tree you can only warm a small slice, so this is what makes the warm window contain what you search for. Measured lift (node eval/bench-hitrate.mjs, 2,000 files):

warm-up cap

arbitrary order

history-ordered

lift

3% of files

1.5%

54.3%

36×

5%

7.8%

56.5%

7.3×

10%

11.3%

62.5%

5.6×

20%

24.8%

68.5%

2.8×

50%

46.3%

80.5%

1.7×

The smaller the slice you can afford to warm, the bigger the win.

Each search records the tokens it saved vs forwarding the raw index response. Check it with /vs-token-safer:savings, vts savings (--graph/--daily/--history), or reset via vts savings-reset.

vs-token-safer savings (local, 1 search(es))
  total saved: ~4,200 tokens vs forwarding raw index responses
  raw → output: 4,340 → 140 tok (~31× smaller)
  est. value: ~$0.01 (@ $3/Mtok — set VTS_USD_PER_MTOK)

That's the caught side. vts discover scans recent sessions for searches that went around the index:

$ vts discover --since 1
  86 code search(es) bypassed vts (Grep×48, Glob×18, grep×12, find×8)
  catch-rate: ~770,333 tok caught (via vts) vs ~28,692 still bypassing → 96.4% routed through vts

(Searches the hook blocked don't count as bypasses.) discover is local and read-only — it reads transcript metadata and tool I/O sizes, never ships any of it anywhere. --learn feeds the files past searches hit into the warm-up set, so each session leaves the index warmer.

Prerequisites (details)

  • Node.js ≥ 18 on PATH.

  • C/C++ → clangd ≥ 22 (releases). The clangd 19.1.x bundled with Visual Studio deadlocks indexing real Unreal TUs in server mode; vts warns on an older one. Needs a compile_commands.json.

  • C#/.NET → a Roslyn LSP. Install the VS Code C# extension (ms-dotnettools.csharp) — vts auto-detects Microsoft.CodeAnalysis.LanguageServer and its runtime from the bundle. Fallback: dotnet tool install --global csharp-ls. Needs a .sln/.csproj.

  • JS/TS → typescript-language-server, Python → pyright. Ship as plugin deps, install automatically on the first session (one-time ~50 MB; JS/TS wants Node 20+, skipped on 18).

  • Mixed repo? A query that targets a file uses that file's own language backend — a .py/.ts inside a C++/C# (clangd/roslyn-rooted) tree gets pyright/typescript automatically, so vts works in a UE tree with a Python tooling dir without a manual backend=.

clangd needs a compile database:

  • Unreal: <UE>/Engine/Build/BatchFiles/RunUBT … -mode=GenerateClangDatabase. If targets build with clang-cl, add -Compiler=VisualCpp or it fails clang-toolchain validation.

  • CMake: -DCMAKE_EXPORT_COMPILE_COMMANDS=ON.

No compile DB yet? You still get answers — search_symbol falls back to a bounded literal text search, labeled as such, and the first result carries a one-time advisory. The one-command fix: vts_gen_compile_db (CLI vts gen-compile-db) assembles the exact UBT command (finds the .uproject, derives the <Name>Editor target, locates the engine, adds -Compiler=VisualCpp). Dry-run by default; apply=true runs UBT and parks the DB outside the source tree (~/.vs-token-safer/db/<project>, with clangd's .cache/ next to it, so git/p4 reconcile never see an artifact). inTree=true keeps the classic project-root layout, protected by a VCS-ignore guard.

Not published to npm — install vts from a clone:

git clone https://github.com/JSungMin/vs-token-safer
cd vs-token-safer/server && npm install && npm link   # provides `vts`
# or run directly: node /path/to/vs-token-safer/server/cli.js symbol --q SpawnActor --projectPath /path/to/proj

Configuration

Settings live in ~/.vs-token-safer/config.json (read at startup — /reload-plugins after changes). Configure via /vs-token-safer:setup (guided), vts_setup/vts_config tools, or vts setup --projectPath <root> --backend clangd. Backend auto-detects from the root. Precedence: env (VTS_*) > config file > default.

Updating: Claude Code caches the marketplace, so new commits aren't auto-fetched:

/plugin marketplace update vs-token-safer
/plugin update vs-token-safer
/reload-plugins
# then RESTART the session — REQUIRED.

⚠️ A new version only takes full effect after a session restart. /reload-plugins updates hooks/commands/skills, but the running vs-search MCP server serves the old tool code until you quit and reopen. Version history: Releases.

Precedence: VTS_* env > ~/.vs-token-safer/config.json > default.

Config key

Env var

Default

Meaning

projectPath

VTS_PROJECT_PATH

cwd

Project root (where the compile DB / .sln lives).

backend

VTS_BACKEND

auto

clangd | roslyn | typescript | pyright.

maxResults

VTS_MAX_RESULTS

60

Cap on returned file:line locations.

VTS_COMPACT_RESULTS

1

0 restores one-location-per-line output.

VTS_MAX_BACKENDS

2

Max concurrently-live language servers (LRU-evict past the cap).

VTS_BACKEND_IDLE_MS

300000

Idle language server shut down after this (0 = off).

clangdCmd

VTS_CLANGD_CMD / VTS_CLANGD_ARGS

clangd

clangd executable (persist via vts setup --clangdCmd <path> — VS-bundled 19.1.x deadlocks UE, use ≥ 22) / args.

VTS_ROSLYN_DLL

auto

Path to a specific Microsoft.CodeAnalysis.LanguageServer.dll.

VTS_ROSLYN_CMD / VTS_ROSLYN_ARGS

auto → csharp-ls

Override the C# LSP.

VTS_TS_CMD / VTS_PY_CMD (+ _ARGS)

bundled

Override the JS/TS / Python LSP.

VTS_TS_OPEN_CAP / VTS_PY_OPEN_CAP

60

Files the JS/TS / Python warm-up opens.

VTS_LSP_TIMEOUT_MS

30000

Per-request LSP timeout. Raise for a cold, large index.

VTS_LSP_INDEX_WAIT_MS

120000

How long the clangd warm-up waits for background-index completion.

VTS_CLANGD_OPEN_CAP

100

Files the cold warm-up opens to prime clangd.

VTS_CLANGD_WARM_CAP_PERSISTED

8

Open cap when a persisted .cache/clangd index exists.

VTS_CLANGD_PERSISTED_WAIT_MS

60000

Cap on how long a query polls a still-loading persisted index.

VTS_CLANGD_PERSISTED_FLOOR_MS

3000

Brief floor before the first query starts polling.

VTS_CLANGD_INDEX_PRIORITY

normal

clangd background-index priority (background = idle-CPU-only).

VTS_CLANGD_JOBS

cores-1

clangd async/index workers (-j).

VTS_PREWARM

on (if projectPath)

MCP server pre-warms at boot; 0 disables.

VTS_PREWARM_BACKENDS

auto

auto / all / comma list — which backends to pre-warm.

VTS_WARM_CAP_RATIO / VTS_WARM_CAP_MAX

0.1 / 300

Adaptive warm-up open-cap (fraction of a language's files, clamped).

VTS_CLANGD_REMOTE

Address of a shared/prebuilt clangd index server.

VTS_QUERY_HISTORY / VTS_INCLUDE_GRAPH

~/.vs-token-safer/…

Warm-up ordering caches.

VTS_CENTRALITY_MAX / VTS_CENTRALITY_BUDGET_MS

20000 / 400

Include-centrality scan bounds (0 disables / cache-only).

VTS_ENFORCE

1

0 lets Bash code-grep through (escape hatch).

VTS_REWRITE

1

0 makes the hook block a Bash code-grep instead of rewriting it.

VTS_GREP_BLOCK

1

0 reverts the Grep/Glob tool escalation from block to warn-only.

VTS_EDIT_STEER

1

0 hides the one-line hint (on a focused search_symbol/goto_definition result) pointing at the symbol-edit tools. VTS_EDIT_STEER_MAX (10) caps the result size that gets it.

VTS_EDIT_WARN

1

0 silences the model-visible nudge when a built-in Edit/MultiEdit replaces or adds a whole declaration (it points at replace_symbol_body / insert_after_symbol). Sub-declaration tweaks are never nudged.

VTS_TEXT_STEER

1

0 hides the one-line hint appended to a search_text result whose query is really a symbol/class usage hunt (a Foo<Bar> template arg, :: scope, or CamelCase/snake identifier) — it points at find_references / search_symbol, which are semantic and complete (no 4s time-box). Fires only when the scan was truncated or the query carries a <>/:: cue.

VTS_EDIT_BLOCK_AFTER

0 (off)

Opt-in. Set ≥1 to escalate the warn to a one-time block on a safe insert after that many consecutive ignored nudges (then it resets — fire-once, not a wall). Default off: a persistent block trapped the agent (it fought the wall with Edit retries instead of switching). A replace always stays a warn; VTS_GREP_BLOCK=0 also holds it to warn.

VTS_EXCLUDE_COMMANDS

Comma list of executables to exempt (also excludeCommands in config).

VTS_COMPACT_VCS

1

0 stops rerouting read-only git/p4 to the compacted wrapper.

lang

VTS_LANG

auto

Hook message language: ko / en (auto-detects from OS locale).

VTS_TEE / VTS_TEE_DIR

truncate

Recovery file for a capped find_files/search_text result.

VTS_USD_PER_MTOK

3

$/Mtok rate for the estimated-value line (informational).

VTS_CLAUDE_PROJECTS

~/.claude/projects

Where vts discover looks for transcripts.

VTS_DB_DIR

~/.vs-token-safer/db

Out-of-tree home for generated compile DBs.

Symptom

Cause

Fix

/vs-token-safer:setup not in autocomplete

Plugin not installed (only marketplace added), or stale

/plugin install vs-token-safer@vs-token-safer/reload-plugins.

First clangd query very slow

Per-spawn clangd cost on a UE-scale tree (cold index, or re-validating a persisted one)

Keep the MCP server running so clangd spawns once. Tune VTS_CLANGD_PERSISTED_WAIT_MS / VTS_LSP_INDEX_WAIT_MS.

clangd query never returns (hangs) on UE

clangd 19.1.x bundled with VS deadlocks on UE TUs

Install clangd ≥ 22, point VTS_CLANGD_CMD at it.

GenerateClangDatabase fails: "Unable to find valid C++ toolchain for Clang x64"

Targets build with clang-cl

Add -Compiler=VisualCpp to the UBT command.

clangd resolves only header-free symbols

Compile DB has no include dirs

Use a UBT-generated DB (it includes the paths).

No C# results / "No backend resolved"

Roslyn engine not found

Install the VS Code C# extension, or csharp-ls; or set VTS_ROSLYN_DLL / VTS_ROSLYN_CMD.

No JS/TS or Python results

Bundled LSP didn't install (offline first run)

Re-run the session, or set VTS_TS_CMD / VTS_PY_CMD.

Code search blocked when you wanted plain grep

The hook is steering you to the index

VTS_ENFORCE=0 lets grep through.

Wrong backend picked

Multiple project files under the root

Pin VTS_BACKEND=clangd (or pass backend per call).

Status & safety

  • clangd & Roslyn live-verifiedsearch_symbol/find_references/goto_definition confirmed against real clangd (incl. a real Unreal 5.x game project end-to-end) and Microsoft.CodeAnalysis.LanguageServer. Needs clangd ≥ 22 and a correct compile DB.

  • Local-only, nothing uploaded. The hook only inspects the command string (honors VTS_ENFORCE=0); the language server runs over stdio; the only outbound call is the first-run npm install of the MCP SDK. It writes only its config + a local savings ledger under ~/.vs-token-safer/. See SECURITY.md and PRIVACY.md.

  • Savings/benchmark numbers are response-shaping (raw index → capped); savings vs grep are larger (BENCHMARK.md).

Contributing

Issues and PRs welcome — bug reports, new backends/engines, language mappings, docs. Keep PRs small, evidence-backed, and free of proprietary data (real paths/symbols/project IDs); add an eval/run.mjs guard for any new code path. See CONTRIBUTING.md. If this saved you tokens, a star helps others find it. ⭐

License

MIT © 2026 JSungMin

Install Server
A
license - permissive license
A
quality
B
maintenance

Maintenance

Maintainers
Response time
0dRelease cycle
46Releases (12mo)
Commit activity

Latest Blog Posts

MCP directory API

We provide all the information about MCP servers via our MCP API.

curl -X GET 'https://glama.ai/api/mcp/v1/servers/JSungMin/vs-token-safer'

If you have feedback or need assistance with the MCP directory API, please join our Discord server