Get purchase transaction

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

Annotations already convey readOnlyHint, idempotentHint, and non-destructive behavior, so the bar is lower. The description adds useful return-field context but does not disclose behavior for missing ids, administration scoping, or any edge-case handling. No contradiction with annotations exists.

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?

One sentence, front-loaded with the operation and resource, no filler or redundant content. Every word earns its place.

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 simple read-only fetch with one required parameter and annotations covering the safety profile, the description is nearly complete. It names the return fields in lieu of an output schema. The main missing context is explicit routing to the list sibling and error/not-found behavior.

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 50%; administration_id is documented in the schema, but purchase_transaction_id is not. The description's 'by id' adds little beyond the parameter name and does not clarify the id's format, type constraints, or how administration_id relates to the lookup.

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?

Description states a specific verb and resource: 'Retrieve one purchase transaction by id,' and also names the returned attributes (amount, state, document it pays). This clearly differentiates it from the sibling list_purchase_transactions by emphasizing singular retrieval by id.

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?

The description implies the tool should be used when a specific purchase transaction is needed by id, but it does not explicitly state exclusions or direct the agent to list_purchase_transactions when the id is unknown. Some usage context is conveyed, but alternatives are not named.

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