Sources and health

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

Annotations already mark the operation read-only and open-world. The description adds valuable interpretive context: absence of data may mean a source was never polled, not that it is empty, and it surfaces failing sources. This goes beyond what the annotations alone convey.

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 with no filler. The first sentence front-loads the catalogue and health facts; the second adds a concise, important usage caution. Every sentence 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?

For a zero-parameter read-only tool with an output schema and open-world annotation, the description fully covers why an agent would invoke it and how to interpret one of its key signals. Nothing essential 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 tool has zero parameters, so the baseline for this dimension is 4. There is no parameter ambiguity for the description to resolve, and no additional parameter meaning is needed.

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?

Describes the resource ('the catalogue and its health') and the specific facts it exposes: which sources exist, language, tags, last-answered time, and failing status. It is distinguishable from content-focused siblings like wire_read or wire_search, though it lacks an explicit action verb such as 'list' or 'retrieve'.

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?

Gives an explicit use case: 'Read this before concluding a topic is quiet.' It also warns about the distinct meaning of a never-polled source versus one with no content. It does not name alternatives or state when not to use the tool, but the context is clear.

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