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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the bar is lower. The description adds useful content-level context by specifying the output resource type (ak.capability.v1) and the concrete fields returned, including the task-independent ak.offer.v1 offer. It stops short of noting pagination, caching or rate behavior, so it is good but not exhaustive.

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?

Front-loads what the card is, then usage, then exclusions, then input, then output — a logical order with no filler. It is dense to the point of being a run-on paragraph, but every clause carries information an agent needs.

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?

Although there is no output schema, the description compensates by naming the returned contract (ak.capability.v1) and its major field groups. Combined with fully covered input schema and rich annotations, an agent has everything needed to select and invoke this tool correctly.

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 coverage is 100%, so the accepted id/URI/slug formats are already documented, establishing a baseline of 3. The description goes beyond the schema by telling the agent where to source the value (from a search, an evaluation or a page), which is genuinely useful routing information not present in the structured field.

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?

Names a specific verb+resource (get a capability card) and enumerates exactly what the card contains: purpose, conditions, permissions, price, evidence, trust checks, links and an offer. It explicitly distinguishes itself from siblings by naming evaluate_capability and get_benchmark as the wrong choices.

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?

Provides explicit 'Use when' conditions (you can name a capability and want its facts, or want to check conditions an evaluation asked about) and 'Not for' exclusions that route to the correct alternatives (evaluate_capability for a task answer, get_benchmark for full records). No inference is required.

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