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

With no annotations provided, the description carries the full burden. It implies a read operation via 'Return' and 'GET', which is a useful behavioral signal. It also notes that the 'stacks' include value is 'deprecated, always empty', adding nuance. However, it does not explicitly state that the operation is side-effect free, nor does it disclose anything about response size, pagination, or rate limits. This is adequate but not comprehensive.

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 two sentences long, with the purpose front-loaded in the first sentence. The second sentence summarizes the parameters in a compact way without unnecessary detail. It earns a 4 because it is efficient and to the point, though it loses one point for not explicitly routing the agent to alternatives (which would enhance structure).

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 tool that returns a catalog index, the description fails to specify the actual return structure (e.g., whether it's a list of objects, slugs, or a hierarchical tree). It mentions 'compact slug-only mode' implying a default richer format, but without any detail on fields or pagination, an agent cannot reliably predict the output. Given the absence of an output schema, the description should have been more explicit about what 'index' contains. This is a notable gap, so 3 is fair.

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 describes all three parameters with full coverage (100%). The description's second sentence ('Optional category slug, include list, and compact slug-only mode') essentially restates the schema content without adding new meaning. The 'deprecated, always empty' note is already in the schema for 'include', so the description adds no value beyond the schema. Baseline 3 is appropriate.

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 clearly states a verb ('Return') and a resource ('filterable aicoolies catalog index'), which is specific. It also adds an API equivalent ('Equivalent to GET /api/agents/context') that grounds the purpose. However, it does not explicitly contrast with siblings like get_catalog_meta; the word 'index' implies distinction, but it's inferred rather than stated, so it's not a perfect 5.

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 guidance on when to use this tool versus siblings like search_tools or get_catalog_meta. The description only lists optional parameters, not the context in which this index is preferred. The lack of any 'use when' or 'use instead' signal means an agent must reason from the name alone, which is insufficient.

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