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

Annotations include readOnlyHint=true, so the read-only nature is already declared. The description adds context about requiring an exact event id and producing a bounded chain, which is useful. However, it does not describe the return format, what 'bounded' means beyond the depth parameter, or any edge-case behavior. With the annotation covering safety, the description provides some additional value but not rich behavioral context.

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 brief and front-loads the core action: 'Expands one exact disaster event id into a bounded related-event chain.' It includes a usage guideline in the same breath. The opening 'Free linked-disaster helper' is slightly vague and could confuse, but it does not distract significantly. Overall, it is concise and well-structured, though not as tight as a pure two-sentence example.

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?

With no output schema, the description does not need to explain return values, but it also does not hint at the structure of the 'chain' (e.g., nested events or flat list). The schema and annotations are thorough for parameters and safety, but the description is missing guidance on what the response looks like or any edge cases (ambiguous ids, depth behavior). This leaves some gaps for a tool that returns a possibly complex chain.

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%, with each parameter clearly described, including examples and defaults (e.g., event_id mentions 'NOAA-SIG-2', cross_type_only explains default true). The tool description adds little beyond what the schema already provides, mentioning 'supported pack' which is also in pack_id. Baseline 3 applies due to high schema coverage; the description does not meaningfully add parameter semantics.

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 tool's function: 'Expands one exact disaster event id into a bounded related-event chain.' It specifies the resource (exact disaster event id), the action (expands), and the output (bounded related-event chain). It also distinguishes from siblings by emphasizing it requires an exact id, unlike search_disaster_links, and by focusing on chain expansion rather than direct links.

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 provides a clear usage condition: 'Use this only when you already have an exact event id from a supported pack...' This tells the agent when to use the tool. However, it does not explicitly name alternative tools for cases where an exact id is lacking, nor does it state when not to use it in relation to siblings like search_disaster_links or get_disaster_links_for_event.

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