Mutmut MCP
Server Configuration
Describes the environment variables required to run the server.
| Name | Required | Description | Default |
|---|---|---|---|
| venv_path | No | Path to virtual environment (optional) |
Instructions
Guidance the server publishes about itself, which clients place ahead of the tool catalog so the model reads it before choosing anything.
This server publishes no instructions, or was last inspected before Glama recorded them.
Capabilities
Features and capabilities supported by this server
Protocol revision2025-11-25
| Capability | Details |
|---|---|
| tasks | {
"list": {},
"cancel": {},
"requests": {
"tools": {
"call": {}
},
"prompts": {
"get": {}
},
"resources": {
"read": {}
}
}
} |
| tools | {
"listChanged": true
} |
| prompts | {
"listChanged": false
} |
| resources | {
"subscribe": false,
"listChanged": false
} |
| experimental | {} |
Tools
Functions exposed to the LLM to take actions
| Name | Description |
|---|---|
| run_mutmutA | Run a full mutation testing session with mutmut on the specified target. This tool initiates mutation testing on the given module or package. You can provide additional mutmut options as needed. The output includes a summary of mutations tested, including counts of killed, survived, and timed-out mutations. If a virtual environment path is provided, mutmut will be run using the binaries from that environment to ensure compatibility with project-specific dependencies. Args: target (str): The module or package to run mutation testing on. options (str): Additional command-line options for mutmut (e.g., '--use-coverage'). Defaults to empty. venv_path (Optional[str]): Path to the project's virtual environment to use for running mutmut. Defaults to None. Returns: str: Summary of the mutation testing run, or error message if the run fails. |
| show_resultsC | Display overall results from the last mutmut run using the mutmut CLI. Returns the plain text output. |
| show_survivorsC | List details of surviving mutations from the last mutmut run using the mutmut CLI. Returns the plain text output. |
| rerun_mutmut_on_survivorB | Rerun mutmut on specific surviving mutations or all survivors after test updates using the mutmut CLI. Returns the plain text output. |
| clean_mutmut_cacheB | Clean mutmut cache using the mutmut CLI (if available), otherwise remove .mutmut-cache file. Returns the plain text output or confirmation message. |
| show_mutantB | Show the code diff and details for a specific mutant using mutmut show. Args: mutation_id (str): The ID of the mutant to show. venv_path (Optional[str]): Path to the virtual environment, if any. Returns: str: The output of 'mutmut show '. |
| prioritize_survivorsA | Prioritize surviving mutants by likely materiality, filtering out log/debug-only changes and ranking by potential impact. Returns a sorted list of survivors with reasons for prioritization. |
Prompts
Interactive templates invoked by user choice
| Name | Description |
|---|---|
No prompts | |
Resources
Contextual data attached and managed by the client
| Name | Description |
|---|---|
No resources | |
TDQS
Scored across 7 tools
Each tool has a distinct purpose: run_mutmut initiates testing, show_results displays overall results, show_survivors lists survivors, show_mutant shows specific mutant details, rerun_mutmut_on_survivor retests survivors, prioritize_survivors ranks survivors, and clean_mutmut_cache manages cache. There is no overlap or ambiguity in functionality.
All tools follow a consistent snake_case naming pattern with clear verb_noun structures (e.g., run_mutmut, show_results, clean_mutmut_cache). The naming is predictable and readable throughout the set.
With 7 tools, this server is well-scoped for mutation testing with mutmut. Each tool serves a specific role in the workflow, from running tests to analyzing results, without being overly sparse or bloated.
The tool set provides complete coverage for the mutmut domain: it includes core testing (run_mutmut), result inspection (show_results, show_survivors, show_mutant), survivor management (rerun_mutmut_on_survivor, prioritize_survivors), and maintenance (clean_mutmut_cache). There are no obvious gaps in the mutation testing lifecycle.