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

Annotations already declare readOnlyHint=true, openWorldHint=false, and destructiveHint=false. The description adds a meaningful cost model, disclosing that only successful calls are charged and specifying payment modes. This is valuable context beyond the annotations, though 'autonomous x402 call' is left unexplained.

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 short sentences with no fluff. However, leading with the pricing model rather than the tool's core purpose is a slight structural misstep, since the most important information for selection is the purpose.

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 one-parameter entity-resolution tool with annotations covering safety, the description covers the core purpose and cost, which is adequate. It lacks query format details, output shape, and failure semantics, but given the tool's simplicity this is a moderate gap, not a fatal one.

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 single parameter 'query' has 0% schema description coverage. The description gives it minimal semantic meaning ('a horse identity') but does not specify format, examples, or accepted identity types (e.g., name, ID, alias), leaving the agent to guess what to pass.

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 verb ('resolve') and resource ('horse identity against Horse Truth profiles'), clearly indicating an entity-resolution lookup. It doesn't fully clarify what 'resolve' entails or contrast with siblings like horse_snapshot, but it is distinct enough for an agent to differentiate.

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?

No guidance is given for when to use this tool versus siblings such as horse_snapshot or horse_intelligence. The cost note implies a paid operation, but there is no explicit condition like 'use this when you need to canonicalize an identifier' or 'prefer this over horse_snapshot when...'.

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