list_repos

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

The readOnlyHint annotation already communicates safety, so the description adds value by detailing the exact return fields: repo name, HEAD SHA, dataset count, total rows, and dataset names. This goes beyond the annotation and gives the agent a concrete expectation of the output, though it omits ordering or pagination details.

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?

Two sentences, no filler, and information-dense. The first sentence states the action and scope; the second enumerates the output fields. Every word earns its place.

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 zero parameters, a readOnly annotation, and a clear enumeration of return fields, the description fully specifies the tool's behavior. No output schema is needed because the description already tells the agent exactly what will be shown for each repo.

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 zero parameters, so the schema is fully covered and no parameter explanation is needed. The description's mention of return fields further clarifies what each repo entry includes, making the tool predictable without params.

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 uses a specific verb ('List') and resource ('GitHub repositories') with a clear scope ('indexed via index_repo'). It also distinguishes itself from siblings like list_datasets by explicitly mentioning repositories and their data composition.

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 phrase 'indexed via index_repo' clearly implies this tool is for repos that have been previously indexed, providing context for when it applies. It doesn't explicitly name alternatives or exclusions, but the natural contrast with list_datasets and index_repo is evident from the surrounding tool set.

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