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

With no annotations, the description carries the burden. It discloses that the tool maps projects to mentioning repos and gives a quick reference picture, but it does not mention output format, direction of the dependency, or any limitations.

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?

Three short sentences, front-loaded with the core behavior and use case; 'Celestia-specific' is a useful scope qualifier. No filler, though the second sentence could be folded into the first.

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 single-parameter tool with no output schema, the description is largely sufficient: it names the input, the transformation, and the user need. It could add return-shape details, but nothing essential to selecting or invoking the tool is missing.

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?

The input schema already fully describes topic at 100% coverage, so the baseline is 3. The description adds a bit by explaining that the topic selects ecosystem_projects and that the output connects to GitHub repos, clarifying what the single parameter actually drives.

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 states a specific operation ('Map ecosystem_projects matching a topic to the GitHub repos that mention them') with clear resources and output. The use case 'who else is building around X?' differentiates it from generic list/search siblings.

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 implies when to use the tool with 'Useful for...', and the Celestia-specific note gives context. However, it does not explicitly say when not to use it or how it differs from nearby siblings such as find_similar_projects or list_ecosystem_projects.

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