jules_sources

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

The annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds behavior the annotations don't cover: it states that the tool is free, that the result feeds jules_start's `repo` argument, and it documents the empty-state case (no repo connected, with the link where the user connects GitHub).

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?

It is front-loaded with the purpose and prerequisite, then a clearly delineated 'Returns:' block. Some of the return text overlaps with the existing output schema, and 'Read-only and free' partially restates readOnlyHint, so it is not entirely free of redundancy.

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?

For a zero-parameter, read-only tool, the description covers purpose, prerequisite ordering, the value to hand to the next tool, and the failure/empty state. Nothing an agent needs in order to call it and use its result is missing; the return-format detail is a bonus beyond the output schema.

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?

There are no input parameters, so the baseline is 4. The description goes a step further by explaining how the returned value maps onto another tool's parameter ('to pass as `repo` to jules_start'), which is meaning the empty input schema cannot convey.

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 opens with a specific verb and resource: 'List the GitHub repositories the user has connected to Jules.' It also identifies Jules as Google's cloud coding agent, which distinguishes this tool from the gemini_* siblings and from jules_start/jules_status without opening any schema.

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?

It states the exact call ordering ('Call it before jules_start') and the condition that enforces it ('Jules can only work on repositories listed here'), plus the reason for calling ('to get the exact repo name'). This is explicit when-to-use and a hard prerequisite, with the consumer tool named.

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