Jules MCP Server

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

With no annotations provided, the description carries full burden. It discloses key behavioral traits: it creates a session that automatically creates a PR when work is complete, and mentions checking the 'outputs' field for the PR URL. However, it doesn't cover important aspects like authentication needs, rate limits, error conditions, or what happens if the session fails.

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

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

The description is well-structured with clear sections (purpose, parameters, returns) and front-loaded information. Most sentences earn their place, though the parameter explanations could be slightly more concise. The overall length is appropriate for a 4-parameter tool.

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

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

Given the tool's complexity (session creation with PR outcome), no annotations, 0% schema coverage, but presence of an output schema, the description does reasonably well. It explains the purpose, parameters, and what to expect in returns, though could benefit from more behavioral context about the session lifecycle and error handling.

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

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

With 0% schema description coverage, the description must compensate. It provides meaningful semantics for all 4 parameters: prompt (description of changes), source (resource name of repository), branch (optional base branch), and title (optional title). It adds value beyond the bare schema by explaining what each parameter represents and providing examples for source.

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

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

The description clearly states the tool creates a session that results in a pull request, specifying it's a convenience wrapper around create_session with the specific purpose of creating PRs. It distinguishes from sibling tools like create_session by emphasizing the PR outcome and from list_sessions/get_session by being a creation tool rather than retrieval.

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

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

The description provides clear context for when to use this tool (to create sessions that result in PRs) and mentions it's a wrapper around create_session, implying an alternative. However, it doesn't explicitly state when NOT to use it or compare it to other sibling tools like approve_plan or send_message.

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