Create Jules Coding Session

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

With no annotations, the description carries the burden and discloses useful traits: 'runs in an isolated cloud VM' and 'typically completes tasks in 5-60 minutes depending on complexity'. This adds behavioral context beyond the schema. It does not explicitly state that code changes will be made, but 'coding task' implies it, and the schema covers autoApprove/autoCreatePR behavior.

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 three concise sentences, each earning its place: purpose, user action, and execution context. It is front-loaded with the main intent and contains no filler or repetition, making it easy to parse quickly.

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?

The description covers the tool's essence and provides timing expectations, but since there is no output schema, it does not explain what the tool returns (e.g., session ID) or how to track progress. While sibling tools exist for status, the description does not mention next steps, leaving the agent to infer the post-creation workflow.

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?

Schema coverage is 100%, so baseline is 3. The description reinforces that 'prompt' should be detailed and identifies repoOwner/repoName as 'the repository to work on', but it does not add unique meaning beyond the schema. The schema already provides individual parameter descriptions, so the description adds minimal extra semantic value.

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 starts with 'Start a new asynchronous coding task with Jules' which clearly identifies the action and resource. It distinguishes this creation tool from sibling tools like jules_list_sessions, jules_get_status, and jules_delete_session by focusing on initiating a new session rather than managing existing ones.

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 gives clear context for when to use: when you need to start an asynchronous coding task, providing a detailed task description and repository. It implies the async nature and typical duration, which helps the agent decide. However, it does not explicitly mention alternatives or when not to use it, though siblings are clearly different types of operations.

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