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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so no safety caveats are needed. The description goes beyond annotations by disclosing that a case number can be used without an account ('No account is needed to give a case number'), which is a meaningful behavioral boundary. It also details the return contents, compensating for the lack of an output schema.

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 sentences, each with a distinct job: what it returns, when to use it, and how to identify the case. The return payload is front-loaded before the usage guidance, and no sentence is filler. It is dense but efficient.

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 read-only status tool with deep annotation coverage and a 100% documented schema, the description is nearly complete: it covers return content, triggering use cases, and parameter selection. It does not discuss edge cases like multiple matches or error handling, but those are minor for this simple, safe operation.

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 100%, so the baseline is 3. The description adds value by explaining the identification logic among parameters: case_number (optionally with court) identifies a case directly, while matter_id identifies a case already saved to the account. This relational guidance is not fully present in the individual schema descriptions and helps an agent choose the right parameter.

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 uses a specific verb ('Return the current posture of a federal case') and enumerates the exact contents: assigned judge, magistrate judge, filing date, open/terminated status, cause of action, nature of suit, docket entry count, and last docket activity. This level of specificity clearly differentiates it from siblings like get_case_deadlines or get_case_documents, which serve related but distinct purposes.

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 gives explicit trigger conditions: 'Use this when a user asks about the status of their case, who the judge is, whether a case is still open, or what a case is about.' This is clear and actionable context. However, it does not name sibling tools as alternatives or state when not to use it, so it stops just short of the full 5.

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