# io.github.vola-trebla/v8-cpu-profile-decoder-mcp (npm · v8-cpu-profile-decoder-mcp)

MCP server that decodes V8 CPU profiles into token-efficient bottleneck summaries for AI agents

- Trust score: 69/100 (medium)
- Change this week: +25
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-08-03

## Components

- npm · `v8-cpu-profile-decoder-mcp`: 69/100 (this document), [markdown](https://verifymcp.io/servers/vola-trebla-v8-cpu-profile-decoder-mcp/v8-cpu-profile-decoder-mcp.md), [page](https://verifymcp.io/servers/vola-trebla-v8-cpu-profile-decoder-mcp/v8-cpu-profile-decoder-mcp)

## Channel facts

- Registry: `npm`
- Package: `v8-cpu-profile-decoder-mcp`
- Version: `0.3.0`
- Transport: `stdio`

## Trust breakdown

How this component scores in each security and reliability category. Every signal is checked automatically from public evidence about the published package, including repeated runs of it in an isolated sandbox, and we only credit what we can confirm. Scores are 0–100 per category. Scoring method: https://verifymcp.io/docs/scoring (what has changed: https://verifymcp.io/docs/scoring/changelog)

Scored 2026-08-03.

- **Supply Chain Security**: 87/100
  - No malware found by supply-chain analysis.
  - Only part of the dependency tree could be resolved (95 of 99), so this covers what we could see, not the whole tree.
  - No install/post-install scripts declared.
  - Only part of the dependency tree could be resolved (95 of 99), so this covers what we could see, not the whole tree.
- **Provenance & Transparency**: 45/100
  - Source repository is publicly reachable at the declared URL.
  - Provenance check failed: no build-provenance attestation is published.
  - Clear OSI-approved license (MIT).
  - Actively maintained (last published 75 days ago).
  - Disclosure check failed: no security disclosure policy was found in the source repository.
- **Schema Quality & AI Usability**: 75/100
  - AI-judged instruction clarity (excellent).
  - Context-footprint check failed: tool/resource definitions use about 986 tokens (~164/item across 6 items; 6 tools + 0 resources), over budget; trim descriptions and params.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 23/100
  - Stability observed for 7 of 30 days with no destabilising changes; credit accrues until the full window elapses.
- **Tool Coverage**: 100/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 100% of tool parameters carry a description.
- **Capabilities**: 100/100
  - Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.

## Install

### Claude

```bash
claude mcp add vola-trebla-v8-cpu-profile-decoder-mcp -- npx -y v8-cpu-profile-decoder-mcp
```

### Codex

```bash
codex mcp add vola-trebla-v8-cpu-profile-decoder-mcp -- npx -y v8-cpu-profile-decoder-mcp
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "vola-trebla-v8-cpu-profile-decoder-mcp": {
      "type": "local",
      "command": [
        "npx",
        "-y",
        "v8-cpu-profile-decoder-mcp"
      ],
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add vola-trebla-v8-cpu-profile-decoder-mcp --command npx --arg -y --arg v8-cpu-profile-decoder-mcp
```

### Hermes

```yaml
mcp_servers:
  vola-trebla-v8-cpu-profile-decoder-mcp:
    command: "npx"
    args: ["-y", "v8-cpu-profile-decoder-mcp"]
```

### Other

```json
{
  "mcpServers": {
    "vola-trebla-v8-cpu-profile-decoder-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "v8-cpu-profile-decoder-mcp"
      ]
    }
  }
}
```

## Changelog

Every change recorded for this component, newest first. Days that predate change tracking, or that we cannot explain, say so: "we were watching and nothing happened" and "we were not watching" are different claims.

### 2026-08-03 (score 69, +1)

No change was recorded against any check on this day. Stability & Change Management went from 20 to 23. That category is still filling its 30-day observation window: 6 days of observed history at the previous scan, 7 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-08-02 (score 68, +49)

- [security regression] Provenance: unverified → fail
- [security improvement] Install scripts: unverified → pass
- [security improvement] Known CVEs: unverified → partial
- [security improvement] Malware scan: unverified → pass
- [functional regression] Security disclosure: fail → unverified
- [functional regression] Tool coverage: 100 → unverified
- [functional improvement] Schema quality: unverified → excellent
- [functional improvement] License: unverified → pass
- [functional improvement] Dependency health: unverified → partial
- [functional improvement] Stability: unverified → 0.20
- [functional improvement] Maintenance: unverified → pass
- [functional improvement] MCP protocol: unverified → pass
- [functional] First check of Schema quality: unverified
- [functional] Licence: MIT

### 2026-07-31 (score 19, −7)

- [functional] We updated how we score, so this day's move reflects our rubric, not a change to the server

### 2026-07-30 (score 26, −18)

- [security regression] Malware scan: pass → unverified

### 2026-07-27 (score 44)

First indexed and scored.

## MCP tools (6)

### `extract_hottest_functions` (~307 tokens)

Parses a V8 .cpuprofile file and returns the top N functions ranked by exclusive CPU time (self time). Filters out V8 internals and Node.js built-ins by default, returning only user code. Framework frames (express, next.js, koa, etc.) can be collapsed into a single entry. Recursive calls to the same source location are merged with an instanceCount field. Use this first to identify which functions are consuming the most CPU in a Node.js performance profile.

Input parameters:

- `collapse_frameworks` (boolean): Collapse all frames from known frameworks (express, next.js, koa, fastify, nestjs, react, vue, nuxt, hapi) into a single "<framework> internals>" entry per framework. Prevents dozens of small framewo…
- `collapse_recursion` (boolean): Merge multiple nodes with the same source location (functionName + url + line + column) into one entry. instanceCount shows how many recursive instances were merged (default: true)
- `include_node_internals` (boolean): Include V8 internals and Node.js built-ins in results (default: false)
- `min_self_percent` (number): Minimum self time percentage to include a function (default: 0.5%)
- `profile_path` (string, required): Absolute path to the .cpuprofile file
- `top_n` (integer): Number of hottest functions to return (default: 10)

### `analyze_call_tree_path` (~115 tokens)

Finds all callers of a specific function in a V8 CPU profile and returns how often each caller invoked it. Accepts partial, case-insensitive function name matching. Use to answer: what is calling my slow function and how many times?

Input parameters:

- `function_name` (string, required): Function name to search for (partial match, case-insensitive)
- `profile_path` (string, required): Absolute path to the .cpuprofile file
- `top_callers` (integer): Number of top callers to return (default: 5)

### `correlate_source_code` (~129 tokens)

Maps the hottest functions in a V8 CPU profile back to their original TypeScript source locations using source map files (.js.map). Falls back to compiled JS locations if no source map is found. Use to answer: which TypeScript file and line is the bottleneck actually coming from?

Input parameters:

- `profile_path` (string, required): Absolute path to the .cpuprofile file
- `sourcemap_dir` (string): Override directory to search for .map files (default: same directory as .js file)
- `top_n` (integer): Number of hottest functions to resolve (default: 10)

### `analyze_gc_pressure` (~146 tokens)

Analyses a V8 .cpuprofile for garbage collection overhead. Reports total GC time as a percentage of profiling duration, broken down by GC type (Scavenger = short-lived object pressure, Mark-Sweep/Mark-Compact = old-space pressure, Incremental = high allocation rate). Flags when GC exceeds a configurable threshold and provides a targeted recommendation. Use to answer: is GC the bottleneck, and what kind of allocation pattern is causing it?

Input parameters:

- `profile_path` (string, required): Absolute path to the .cpuprofile file
- `threshold_percent` (number): GC percentage above which exceeds_threshold is set to true and a warning is emitted (default: 10)

### `diff_profiles` (~157 tokens)

Compares two V8 .cpuprofile files (before and after an optimization) and returns per-function CPU time deltas, normalized against each profile's total duration. Frames are matched by call-frame coordinates (functionName + url + line + column), not by transient node IDs, so alignment is stable across profiling sessions. Use to answer: which functions improved or regressed after my change, and by how much?

Input parameters:

- `after_profile_path` (string, required): Absolute path to the optimized .cpuprofile file to compare against the baseline
- `before_profile_path` (string, required): Absolute path to the baseline .cpuprofile file
- `top_n` (integer): Number of top improvements and regressions to return (default: 5)

### `analyze_async_bottlenecks` (~132 tokens)

Detects event-loop overhead in a V8 CPU profile by identifying V8 internal frames that represent async machinery — microtask queue processing, nextTick saturation, and timer/immediate callbacks. These frames are invisible to most profilers but consume real CPU when promise chains are deep or nextTick is overused. Use to answer: is the bottleneck async orchestration overhead rather than synchronous computation?

Input parameters:

- `profile_path` (string, required): Absolute path to the .cpuprofile file
- `threshold_percent` (number): Async overhead percentage above which a warning is emitted in the verdict (default: 10)

## Diagnostics

Captured diagnostic sections: Provenance, Dependencies. The full working is on the page: https://verifymcp.io/servers/vola-trebla-v8-cpu-profile-decoder-mcp/v8-cpu-profile-decoder-mcp#diagnostics

## Score history

- 2026-08-03: 69
- 2026-08-02: 68
- 2026-08-01: 19
- 2026-07-31: 19
- 2026-07-30: 26
- 2026-07-28: 44
- 2026-07-27: 44

## Links

- npm package: https://www.npmjs.com/package/v8-cpu-profile-decoder-mcp
- Socket report: https://socket.dev/npm/package/v8-cpu-profile-decoder-mcp
- Repository: https://github.com/vola-trebla/v8-cpu-profile-decoder-mcp
- Changelog RSS feed: https://verifymcp.io/servers/vola-trebla-v8-cpu-profile-decoder-mcp/v8-cpu-profile-decoder-mcp/changelog.xml
- Changelog JSON feed: https://verifymcp.io/servers/vola-trebla-v8-cpu-profile-decoder-mcp/v8-cpu-profile-decoder-mcp/changelog.json
- HTML version of this page: https://verifymcp.io/servers/vola-trebla-v8-cpu-profile-decoder-mcp/v8-cpu-profile-decoder-mcp