GitHub Actions MCP Server

github_cancel_workflow

Cancel a queued or in-progress GitHub Actions workflow run to halt unnecessary builds and free up CI resources.

Instructions

Cancel a workflow run that is currently queued or in progress.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "owner": "<owner>",
      "repo": "<repo>",
      "runId": "<runId>"
    },
    "name": "github_cancel_workflow"
  }
}

Input Schema

Name	Required	Description
`repo`	Yes	Repository name
`owner`	Yes	Repository owner
`runId`	Yes	Workflow run ID to cancel

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.0.0Aug 1, 2026

TDQS

A3.7/5.0

Behavior3/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full burden. It discloses the destructive action ('cancel') and the precondition of run state, but lacks details on permissions, error conditions, or reversibility, leaving some behavioral ambiguity.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, front-loaded sentence with no wasted words. It clearly and efficiently communicates the action and its precondition.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

The tool is simple, but with no output schema and no annotations, the description must provide more context. It covers the essential purpose and precondition but does not mention expected responses, failure modes, or permission requirements. Adequate for basic use, but with clear gaps.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema descriptions cover 100% of parameters, so the baseline is 3. The description does not add extra meaning beyond the schema, though it does highlight that the runId must refer to a queued/in-progress run, which is a slight contextual addition.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the verb 'cancel' and the resource 'workflow run', and adds a scope condition ('queued or in progress'). This distinguishes it from sibling tools like rerun_workflow or watch_workflow, making the purpose unambiguous.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description implies the tool should be used when a workflow run is queued or in progress, but it does not explicitly state when not to use it or mention alternative tools. The state constraint provides some guidance, but there is no direct comparison to siblings.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Deploy Server