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

The annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the description should add more context, but it doesn't. It says nothing about what data the response has, whether results are paginated, or how to handle a contract with no expenses, and the operation ID has no practical value.

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 same sentence appears twice word-for-word, so the text is bloated and repetitive rather than concise. The operation-ID boilerplate at the end adds no information, and nothing substantive is presented first.

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 two-parameter read endpoint with no output schema and 0% parameter documentation, the description needs to explain what entity is returned and what the query object accepts. It covers neither, so an agent cannot confidently invoke it or interpret the result.

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%, so the description should explain parameter meaning and still does not. contractId is visible only in the route template, and the 'query' object parameter has no formatting options, allowed keys, or expected values documented in either the schema or the description.

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 just repeats the tool name and title by pasting the HTTP route 'GET /api/expenses/contract-period/:contractId' twice. It doesn't say what an 'expenses contract period' is or what the call returns, and a nearby tool, get_expenses_contract_period_overview, covers a similar area, but the description doesn't distinguish this tool from it.

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?

Apart from a brief hint that 'describe_operation provides native request schemas', it gives no guidance on when to use this tool, when not to use it, or which of the many sibling expense or contract tools is the alternative. An agent must infer usage entirely from the route string.

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