Jenkins Ci

A FastMCP server that gives Claude direct access to Jenkins CI/CD via the Jenkins REST API. Trigger builds, stream console output, manage the build queue, poll build status, and abort running builds — all over stdio JSON-RPC with no external Python dependencies beyond FastMCP itself.

This server is one of 13 MCP servers in the claude-workflow-engine ecosystem. When enabled, it gates pull request merges in Step 11 of the pipeline on a successful Jenkins build.

---

Features

• Trigger parameterized and parameterless Jenkins builds
• Get build status for any build number or the latest build
• Stream console output (last 10,000 characters) for any build
• List jobs at the top level or within a folder
• Get detailed job info including health score, recent builds, and queue state
• List recent builds for a job with result and duration
• Abort a running build by job name and build number
• Inspect the live build queue across the entire Jenkins instance
• Poll a build until it completes or a timeout is reached
• Verify Jenkins connectivity and retrieve server metadata
• Supports folder paths (folder/subfolder/job) and URL-encodes all path components
• SSL verification can be disabled for self-signed certificates

---

Tool Reference

Tool	Description	Key Parameters
jenkins_trigger_build	Trigger a build for a job. Uses /buildWithParameters when parameters are provided, /build otherwise.	job_name (str), parameters (optional str, e.g. "BRANCH=main&ENV=staging")
jenkins_get_build_status	Get status of a specific build: result, building flag, duration, URL, timestamp.	job_name (str), build_number (int; use 0 for last build)
jenkins_get_console_output	Fetch the console log for a build. Truncates to last 10,000 characters if larger.	job_name (str), build_number (int; use 0 for last build)
jenkins_list_jobs	List all jobs. Optionally filter to a specific folder.	folder (optional str; omit for top-level jobs)
jenkins_get_job_info	Get detailed job info: description, buildable flag, health score, last build numbers, recent builds.	job_name (str)
jenkins_list_builds	List recent builds for a job with result, duration, and timestamp.	job_name (str), max_builds (int, default 10, max 50)
jenkins_abort_build	Stop a running build immediately.	job_name (str), build_number (int; use 0 for last build)
jenkins_get_queue_info	Get the current build queue: item IDs, job names, blocked status, wait reason.	(no parameters)
jenkins_wait_for_build	Poll a build every 5 seconds until it finishes or the timeout is reached.	job_name (str), build_number (int; use 0 for last build), timeout_seconds (int, default 300)
jenkins_health_check	Verify Jenkins is reachable. Returns version, executor count, mode, and node name.	(no parameters)

---

Installation

1. Clone the repository

git clone https://github.com/techdeveloper-org/mcp-jenkins-ci.git
cd mcp-jenkins-ci

2. Install dependencies

pip install fastmcp

The server uses Python's standard library (urllib, ssl, base64, json) for all Jenkins API calls. No additional HTTP client libraries are required.

3. Register in Claude Code

Add the server to your ~/.claude/settings.json under mcpServers:

{
  "mcpServers": {
    "jenkins-ci": {
      "command": "python",
      "args": ["/path/to/mcp-jenkins-ci/server.py"],
      "env": {
        "JENKINS_URL": "https://jenkins.your-company.com",
        "JENKINS_USER": "your-username",
        "JENKINS_API_TOKEN": "your-api-token"
      }
    }
  }
}

Restart Claude Code after saving.

---

Configuration

The server reads four environment variables at startup. Set them in the env block of your settings.json or export them before running the server manually.

Variable	Required	Default	Description
JENKINS_URL	Yes	—	Base URL of your Jenkins instance, e.g. https://jenkins.company.com
JENKINS_USER	Yes	—	Jenkins username for authentication
JENKINS_API_TOKEN	Yes	—	Jenkins API token (not your password). Tokens bypass CSRF crumb requirements. Generate one at <JENKINS_URL>/user/<username>/configure.
JENKINS_VERIFY_SSL	No	true	Set to false to skip SSL verification for self-signed certificates

To enable this server within the claude-workflow-engine pipeline, also set:

ENABLE_JENKINS=1

---

Usage Examples

Trigger a build

Trigger a build for the "backend-api" job with BRANCH=main and ENV=staging.

Claude calls jenkins_trigger_build with:

• job_name: "backend-api"
• parameters: "BRANCH=main&ENV=staging"

Returns the queue URL where the build is waiting to be scheduled.

---

Check build status

What is the status of build 47 for the "backend-api" job?

Claude calls jenkins_get_build_status with:

• job_name: "backend-api"
• build_number: 47

Returns result (SUCCESS, FAILURE, ABORTED, or null if still running), building, duration_ms, and the build URL.

---

Stream console output

Show me the console output for the last build of "infra/deploy-prod".

Claude calls jenkins_get_console_output with:

• job_name: "infra/deploy-prod"
• build_number: 0

Returns the last 10,000 characters of the build log. If the log was truncated, truncated: true and total_chars indicate the full size.

---

Wait for a build to finish

Wait for build 52 of "backend-api" to complete. Timeout after 10 minutes.

Claude calls jenkins_wait_for_build with:

• job_name: "backend-api"
• build_number: 52
• timeout_seconds: 600

Polls every 5 seconds. Returns result, timed_out, and elapsed_seconds when the build finishes or the timeout is reached.

---

Pipeline Integration

When ENABLE_JENKINS=1, this server participates in Step 11 of the claude-workflow-engine pipeline (PR creation and code review).

Step 11 flow with Jenkins enabled:

1. Implementation is complete (Step 10). A pull request is opened against the target branch.
2. Step 11 calls jenkins_trigger_build to start the CI build for the PR branch.
3. Step 11 calls jenkins_wait_for_build to block until the build completes.
4. If result == "SUCCESS", the pipeline proceeds to post the build status on the PR and moves toward merge.
5. If result != "SUCCESS", the pipeline surfaces the failure and halts automatic merge, prompting the user to inspect the console output or abort.

This pattern ensures no PR is merged without a passing Jenkins build. The build result is also linked back to the associated Jira issue when ENABLE_JIRA=1 is set alongside ENABLE_JENKINS=1.

---

Part of the claude-workflow-engine Ecosystem

This server is one of 13 MCP servers used by claude-workflow-engine, a LangGraph orchestration pipeline for automating Claude Code development workflows.

#	Server	Purpose
1	mcp-session-mgr	Session lifecycle management
2	mcp-git-ops	Git branch, commit, push, diff
3	mcp-github-api	PR creation, merge, issue management
4	mcp-policy-enforcement	Policy compliance and system health
5	mcp-token-optimizer	Token reduction (AST navigation, smart read)
6	mcp-pre-tool-gate	Pre-tool validation and policy checks
7	mcp-post-tool-tracker	Post-tool progress tracking
8	mcp-standards-loader	Coding standards detection and loading
9	mcp-uml-diagram	UML diagram generation (13 types)
10	mcp-drawio-diagram	Draw.io editable diagram generation
11	mcp-jira-api	Jira issue create, transition, link
12	mcp-jenkins-ci	Jenkins CI/CD (this server)
13	mcp-figma	Figma design tokens and component extraction

All servers share the mcp-base package for consistent response formatting, error handling, and tool decoration.

---

Contributing

Contributions are welcome. Please open an issue to discuss the change before submitting a pull request. All changes must include:

• Type hints on all function signatures
• Docstrings for any new tool or helper
• ASCII-only source (cp1252 compatible for Windows)
• No new external dependencies — stdlib only for Jenkins API calls

---

License

MIT License. See LICENSE for details.