get_transaction

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

No annotations are provided, so the description carries the full disclosure burden. It helpfully enumerates the returned fields (id, amount, status, etc.), which compensates for the missing output schema, but it says nothing about auth requirements, error behavior for an unknown/invalid ID, or read-only/safety characteristics.

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?

Two sentences, purpose first, return shape second. The field enumeration is long but earns its place because there is no output schema to document the response.

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 single-parameter read tool with no output schema, the description supplies both the lookup semantics and the full return-field list, which is what an agent needs. Only error/permission behavior is left unaddressed, a minor gap.

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 100% ('The Mercury transaction UUID'), so the schema already documents the sole parameter. The description only restates that lookup is by transaction ID and adds no format or constraint detail beyond the schema.

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?

States a specific verb ('Retrieve') and resource ('a single Mercury transaction') plus the lookup key (transaction ID), which lets an agent distinguish it from list_transactions/list_account_transactions by cardinality. It does not, however, explicitly name those siblings as the alternative.

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 only implied: 'by its transaction ID' signals a single-record lookup versus the list_* siblings, but there is no explicit when-to-use/when-not guidance or named alternative. The agent must infer the routing from the name and cardinality.

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