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

The description aligns with the readOnlyHint annotation by saying 'Retrieve' and does not contradict it. However, it does not add significant behavioral details beyond the annotation, such as side effects or permissions. The added details about the output structure are more about results than behavior.

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 description is a single, front-loaded sentence that efficiently conveys the core functionality. There is no redundant information, and the structure (verb + object + detail of result) is clear and direct.

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 description gives a concrete idea of the output (ancestor chain and branches), which is sufficient for a retrieval tool. It does not mention the novelty filter, but the schema covers that. It is not as complete as the high-scoring example because it lacks any contextual note about when this storyline is relevant, but it is adequate for basic usage.

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?

The schema already covers 86% of parameters with descriptions (e.g., end_timestamp, max_children). The tool description does not add any additional meaning to parameters like novelty or detail, leaving their cryptic descriptions ('Match any', 'essential:minimal') unclarified. Since schema coverage is high, the baseline of 3 is appropriate.

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 clearly states the action ('Retrieve') and the resource ('wire item'), and specifies the exact structure of the result: the linear ancestor chain plus first-degree branches. This distinguishes it from sibling tools like list_wire or search_events, which serve different 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?

No explicit guidance is provided on when to use this tool versus alternatives. It does not mention conditions like 'use when you need the full storyline' or contrast with list_wire or search_developments. The description is self-explanatory but leaves usage inference to the agent.

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