# Compiler Explorer (remote · godbolt.org)

Compile code with thousands of compilers, inspect the assembly, and share godbolt.org links

- Trust score: 63/100 (medium)
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-08-20

## Components

- remote · `godbolt.org`: 63/100 (this document), [markdown](https://verifymcp.io/servers/compiler-explorer-compiler-explorer/godbolt.md), [page](https://verifymcp.io/servers/compiler-explorer-compiler-explorer/godbolt)

## Channel facts

- Endpoint: `https://godbolt.org/mcp`
- Transports: `streamable-http`
- Auth: `none`
- Version: `1.0.0`

## Trust breakdown

How this component scores in each security and reliability category. Every signal is checked automatically against the live server, 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 2026-08-20.

- **Endpoint Security**: 57/100
  - The endpoint's TLS certificate is valid, in date, and uses a strong key.
  - Authorisation not fully verified: no authorisation is required to call this server, and 6 tool(s) never declared a destructiveHint. The MCP spec treats an absent hint as destructive by default, so we cannot call this surface safe.
  - HTTPS is enforced; there's no plaintext access path.
  - HSTS check failed: the Strict-Transport-Security header is absent.
  - DNSSEC check failed: this domain isn't protected by DNSSEC.
- **Transport & Reachability**: 100/100
  - Verified streamable-http transport via a live MCP handshake.
- **Schema Quality & AI Usability**: 73/100
  - AI-judged instruction clarity (excellent).
  - Context-footprint check failed: tool/resource definitions use about 1081 tokens (~154/item across 7 items; 7 tools + 0 resources), over budget; trim descriptions and params.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 7/100
  - Stability observed for 2 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 --transport http compiler-explorer-compiler-explorer https://godbolt.org/mcp
```

### Codex

```toml
[mcp_servers.compiler-explorer-compiler-explorer]
url = "https://godbolt.org/mcp"
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "compiler-explorer-compiler-explorer": {
      "type": "remote",
      "url": "https://godbolt.org/mcp",
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add compiler-explorer-compiler-explorer --url https://godbolt.org/mcp --transport streamable-http
```

### Hermes

```yaml
mcp_servers:
  compiler-explorer-compiler-explorer:
    url: "https://godbolt.org/mcp"
```

### Other

```json
{
  "mcpServers": {
    "compiler-explorer-compiler-explorer": {
      "type": "http",
      "url": "https://godbolt.org/mcp"
    }
  }
}
```

The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.

## 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.

### 2026-08-19 (score 63, +1)

- [functional improvement] Stability: unverified → 0.03

### 2026-08-18 (score 62)

First indexed and scored.

## MCP tools (7)

### `compile` (~257 tokens)

Compile source code and return assembly output, stdout, and stderr

Input parameters:

- `compiler` (string): Compiler ID from list_compilers (e.g. "g161"). If omitted, uses the language's `defaultCompiler` from list_languages.
- `execute` (boolean): Run the program instead of returning assembly. `asm` becomes empty; runtime output goes to top-level `stdout`/`stderr`; compile diagnostics move to `buildResult.stdout`/`stderr`.
- `filters` (object): Output filters
- `language` (string, required): Language ID (e.g. "c++", "c", "rust", "python")
- `libraries` (array): Libraries to link.
- `maxAsmLines` (integer): Cap asm output (default 500 lines).
- `maxStderrLines` (integer): Cap each stderr stream — compile and execute separately (default 100).
- `maxStdoutLines` (integer): Cap each stdout stream — compile and execute separately (default 100).
- `options` (string): Compiler flags (e.g. "-O2 -std=c++20 -Wall")
- `source` (string, required): Source code to compile
- `stdin` (string): Standard input for execution (requires execute=true)

### `list_compilers` (~355 tokens)

List available compilers, optionally filtered by language

Input parameters:

- `includeExperimental` (boolean): With `latestPerMajor: true`, also include experimental compilers (c++ proposal forks, llvm-mos platform variants). Off by default — bloats "newest X" answers.
- `instructionSet` (string): Target architecture filter. Combine with `latestPerMajor: true` for "newest X for arch Y" (e.g. `{language:"c++", instructionSet:"amd64", latestPerMajor:true}`).
- `language` (string): Language ID to filter by (e.g. "c++", "rust", "python")
- `latestPerMajor` (boolean): "Newest X" filter. By release track (stable/nightly/prerelease/experimental): newest stable per (language, instructionSet, semver major); all nightly + prerelease; experimental skipped unless `includ…
- `lean` (boolean): Force id+name only, regardless of count. Useful to browse the catalog before drilling in.
- `match` (string): Case-insensitive AND-of-tokens filter on id and name. Punctuation splits tokens; numeric tokens match whole-word ("gcc 14.1" matches "14.1.0" not "14.10"); alphanumeric tokens substring-match ("g14"…
- `maxResults` (integer): Cap full-detail entries (default 25). Beyond the cap, degrades to lean (id+name only) with a refinement hint.

### `list_languages` (~24 tokens)

List supported languages. Each entry has `defaultCompiler` and `compilerCount`.

### `list_libraries` (~152 tokens)

List available libraries for a given programming language

Input parameters:

- `language` (string, required): Language ID (e.g. "c++", "rust")
- `lean` (boolean): Force id+name only, regardless of count. Useful to browse the catalog before drilling in.
- `match` (string): Case-insensitive AND-of-tokens filter on id, name, and version strings (so "boost 1.88" finds Boost when one of its versions matches 1.88.x). Numeric tokens match version-prefix; alphanumeric substri…
- `maxResults` (integer): Cap full-detail entries (default 25). Beyond the cap, degrades to lean (id+name only) with a refinement hint.

### `lookup_asm_instruction` (~64 tokens)

Look up documentation for an assembly instruction

Input parameters:

- `instruction_set` (string, required): Instruction set architecture (no default — must match the asm dialect being looked up).
- `opcode` (string, required): Assembly instruction mnemonic (e.g. "MOV", "ADD", "JMP")

### `generate_short_url` (~109 tokens)

Create a Compiler Explorer short URL for sharing code with compiler settings

Input parameters:

- `compiler` (string, required): Compiler ID from list_compilers (e.g. "g161", "clang_trunk")
- `language` (string, required): Language ID (e.g. "c++", "c", "rust")
- `libraries` (array): Libraries to include.
- `options` (string): Compiler flags (e.g. "-O2 -std=c++20")
- `source` (string, required): Source code

### `get_shortlink_info` (~120 tokens)

Retrieve source and compiler config from a CE short URL. Compiler entries are returned in the `compile` tool's shape ({compiler, options, libraries:[{id, version}]}). Multi-pane shortlinks (executors, conformance views, CMake trees, per-compiler filters/tools) are flattened — only the basic compile inputs survive.

Input parameters:

- `id` (string, required): Short link ID or full URL (e.g. "G38YP7eW4" or "https://godbolt.org/z/G38YP7eW4")

## Diagnostics

Captured diagnostic sections: TLS, DNSSEC, Authorisation, Transports. The full working is on the page: https://verifymcp.io/servers/compiler-explorer-compiler-explorer/godbolt#diagnostics

## Score history

- 2026-08-20: 63
- 2026-08-19: 63
- 2026-08-18: 62

## Links

- Remote endpoint: https://godbolt.org/mcp
- Repository: https://github.com/compiler-explorer/compiler-explorer
- Website: https://godbolt.org/
- Changelog RSS feed: https://verifymcp.io/servers/compiler-explorer-compiler-explorer/godbolt.xml
- Changelog JSON feed: https://verifymcp.io/servers/compiler-explorer-compiler-explorer/godbolt.json
- HTML version of this page: https://verifymcp.io/servers/compiler-explorer-compiler-explorer/godbolt