hub_repo_info

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

Beyond the readOnlyHint=true and destructiveHint=false annotations, the description discloses important authentication behavior: it sends no auth, avoids reading the local credential store, and explains private repo failure modes. It also clarifies the exact Hub API response shape returned, giving agents a realistic model of the tool's 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 efficiently structured with a one-line purpose, a clear public-only/auth note, an alternative-tools pointer, and compact Args/Returns sections. Every sentence adds useful information, with no filler or repetition of schema fields.

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 tool is a single-parameter read-only metadata fetch, and the description covers the parameter format, auth restrictions, failure mode for private repos, and the structure of the return value. There is no output schema, so the description's explicit listing of returned fields closes the only remaining gap. The complete routing guidance to sibling tools finishes the picture.

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 description coverage is 0%, so the description must carry the parameter documentation burden. It fully compensates by explaining the `repository` parameter and supplying concrete examples ('library/alpine' or 'myorg/myimage'). This is sufficient for an agent to correctly construct the required argument.

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: 'Fetch Docker Hub metadata for a repository.' It further distinguishes itself from relevant siblings by explicitly stating that tag lists belong to `registry_tags` and Hub tag details belong to `hub_tags`. This makes the tool's scope immediately clear and separable from alternatives.

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 explicit usage constraints: public repos only, no auth sent, does not read the local Docker credential store, and private repos return 404/401. It also names the sibling tools to use for tag-related queries, providing clear when-to-use, when-not-to-use, and alternative routing guidance.

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