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

With no annotations supplied, the description carries the full behavioral burden. It does disclose the output shape (machine-readable pass/fail plus evidence), which is valuable, but says nothing about authorization requirements, whether validation is recorded/logged, cost or rate limits, or whether a failure response is a thrown error or a normal result.

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?

Three short sentences, front-loaded with the core action, then the motivating use case, then the return contract. No filler or restatement of the tool name beyond what is necessary.

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?

The absence of an output schema is partly offset by the sentence describing pass/fail and evidence. However, for a five-parameter, auth-bearing tool with zero schema description coverage and no annotations, the definition leaves too much unstated — particularly the version parameter's semantics and what happens on validation failure — to be considered complete.

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 description coverage is 0% across five parameters, including a required accessToken and a length-constrained contractId, yet the description explains none of them. 'Stored, versioned data contract' only loosely gestures at contractId and version; the meaning of version (requested vs. latest), operationId, and the JSON size limit is entirely undocumented.

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 and resource (validate JSON against a stored, versioned data contract) and adds the intended effect: catching missing, changed, or invalid upstream data. It implicitly distinguishes this from validating against an inline schema by emphasizing 'stored, versioned' contract, but never names or contrasts the closest siblings such as json_schema_validate or contract_compare.

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?

Usage is implied rather than prescribed: 'before an AI agent uses it' gives a timing context for calling the tool. There is no explicit when-not guidance and no routing to alternatives (e.g., contract_compare for diffing versions, json_schema_validate for ad-hoc schemas), so an agent must infer the boundary from sibling names alone.

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