@alexsarrell/jenkins-mcp-server v1.3.0

A custom MCP (Model Context Protocol) server for Jenkins integration with Claude Code. Provides 22 tools (20 default + 2 unsafe) for comprehensive Jenkins management including pipeline replay, stage-level logs, structured config reads, parameter introspection, and rich log search.

Why?

The official Jenkins MCP plugin has timeout issues (30s timeouts). This standalone server connects directly to Jenkins REST API via stdio transport and works reliably.

Quick Start

Add to your ~/.claude.json:

{
  "mcpServers": {
    "jenkins": {
      "type": "stdio",
      "command": "npx",
      "args": ["-y", "@alexsarrell/jenkins-mcp-server"],
      "env": {
        "JENKINS_URL": "https://your-jenkins.example.com",
        "JENKINS_USER": "your-username",
        "JENKINS_API_TOKEN": "your-api-token"
      }
    }
  }
}

Restart Claude Code and the jenkins MCP server will be available.

Getting Your API Token

1. Log in to Jenkins
2. Click your username (top right) -> Configure
3. API Token -> Add new Token -> Generate
4. Copy the token

Environment Variables

| Variable | Required | Description | |----------|----------|-------------| | JENKINS_URL | Yes | Jenkins server URL | | JENKINS_USER | Yes | Jenkins username | | JENKINS_API_TOKEN | Yes | Jenkins API token | | JENKINS_ALLOW_UNSAFE_OPERATIONS | No | Set to true to enable unsafe tools (replayBuild, updateJobConfig) |

Unsafe Operations

By default, tools that can execute arbitrary code or modify job configurations are disabled. This includes:

• replayBuild — replays a build with arbitrary Groovy/Pipeline script
• updateJobConfig — overwrites job XML configuration

To enable them, add the env variable to your MCP config:

"env": {
  "JENKINS_URL": "...",
  "JENKINS_USER": "...",
  "JENKINS_API_TOKEN": "...",
  "JENKINS_ALLOW_UNSAFE_OPERATIONS": "true"
}

Tools (20 default + 2 unsafe)

Job Management

• getJobs - List jobs in a folder with status summary
• getJob - Job details, parameters, health, branches (for multibranch pipelines)
• getJobConfig - Get job XML configuration (config.xml)
• getJobParameters - Structured ParameterSpec[] for the job (types, choices, defaults). Use this before triggerBuild to know what to pass.
• describeJob - Structured read of config.xml (SCM url/branch, Jenkinsfile path, parameters, cron, retention) without parsing raw XML.
• previewJobConfig - Generate a config.xml from a structured spec (pipeline / multibranch / folder), optionally diffed against an existing job. Read-only.
• updateJobConfig - Update job XML configuration

Build Operations

• triggerBuild - Trigger builds with optional parameters (string or string[] values for multi-value parameters)
• getBuild - Build details (status, duration, parameters, artifacts, changes); use include to control returned sections
• getBuildLog - Console output with tail / byte-pagination / grep modes (regex + before/after context)
• stopBuild - Abort a running build
• getBuildArtifacts - List build artifacts
• getBuildTestResults - Test results with failure details

Pipeline

• getPipelineStages - Stage overview (names, status, duration)
• getStageLog - Log for a specific pipeline stage
• getPipelineScript - Get Jenkinsfile content from replay page
• replayBuild - Replay a build with optional script modifications
• restartFromStage - Restart pipeline from a specific stage

Discovery & Utilities

• searchBuildLogs - Grep across build logs (regex, before/after context, onlyResults filter, progressive read)
• getQueue - View the build queue
• getQueueItem - Map a queue item ID (returned by triggerBuild) to the build that started, or its current waiting/cancelled state
• enableDisableJob - Enable or disable a job

Multibranch Pipelines

Job paths use / as separator: folder/pipeline/branch

For branches with slashes in the name, use :: separator:

my-pipeline::feature/my-branch

Multi-value parameters

triggerBuild accepts each parameter value as either a string or a string array. The string form is never split on commas — passing "hello, world" sends one value verbatim. For multi-select / ExtendedChoiceParameter (PT_CHECKBOX) parameters, pass an array:

triggerBuild({ jobPath: "x", parameters: { TAGS: ["alpha", "beta", "gamma"] } });

A legacy splitOnComma: true flag preserves the pre-1.3 behaviour (split string values on commas) — deprecated, will be removed in v2.0.

Log search and grep

Both getBuildLog and searchBuildLogs accept a pattern (with optional regex) and before/after context lines. getBuildLog switches to grep mode when pattern is set; otherwise it returns a tail. searchBuildLogs streams logs via Jenkins' progressive-text API and stops early once maxMatchesPerBuild is reached, and an onlyResults: ["FAILURE"] filter prunes builds before fetching their logs.

Notes

• Replay uses Jenkins' form-based replay endpoint (not a clean REST API)
• Restart from Stage requires the Declarative Pipeline plugin
• Config editing works with raw XML — use getJobConfig (or describeJob for a structured subset) to read, modify, then updateJobConfig. For new configs from a spec, use previewJobConfig then paste into updateJobConfig.
• Build logs are capped at 100KB per response; use grep mode or pagination for larger logs
• CSRF crumbs are handled automatically
• Authentication uses HTTP Basic Auth with user API token

License

MIT