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

Annotations already declare readOnlyHint=true, idempotentHint=true, openWorldHint=false and destructiveHint=false, so the safety profile is covered. The description adds some output context (a per-card one-sentence summary plus a count, and the against_measurement taxonomy), which is useful, but it is phrased so confusingly that the behavioral value is diluted.

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 text is a run-on with broken syntax ('each with one sentence, and count, how many there are') and dumps a three-way enumeration of against_measurement values mid-stream. It is neither front-loaded nor economical; the reader has to reconstruct meaning rather than absorb it.

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?

With no output schema, the description carries the full burden of explaining the return shape, and it does attempt this. But the explanation is jumbled and incomplete, giving no clear sense of the record structure, ordering, or what 'count' refers to, so the agent cannot confidently predict the response.

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 takes zero parameters, which establishes the baseline of 4. The schema also states 'No arguments. Returns every domain/card pair,' so there is nothing further for the description to clarify on this dimension.

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 opening clause 'Lists every domain and card this connection serves, each with one sentence, and count' does state a verb and resource. However, the rest of the description veers into garbled commentary about output fields (against_measurement, 'the numbers') rather than reinforcing what the tool is for. It never distinguishes itself from the sibling describe_card, leaving the agent to infer the boundary.

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?

There is no explicit when-to-use, no prerequisites, and no mention of alternatives, despite describe_card and list_solvers being obvious siblings. The agent gets no guidance on when to enumerate cards versus describing a single one.

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