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

Annotations provide readOnlyHint=true, which covers the primary safety concern. The description adds that it is a 'Free linked-disaster discovery helper' and searches 'published' families, but does not disclose additional behavioral traits such as pagination, result shape, or what happens when no filters are provided. Given the read-only annotation, the bar is lower, but the description still lacks substantive 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 two sentences, front-loaded with 'Free linked-disaster discovery helper,' and every clause earns its place: it states what it does, the search criteria, and when to use it. There is no redundancy or filler.

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 search tool with 7 optional parameters and no output schema, the description provides a clear purpose, a usage scenario, and a sense of what is returned (matching link families). It does not detail return values or edge cases, but the schema covers parameter constraints and the annotations cover safety. Missing output format details are a minor gap given the tool's discoverability focus.

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 having its own description. The tool description summarizes parameters as 'event-type direction, optional via-event type, and optional year window,' which adds little beyond the schema. Since the schema already fully documents each parameter, a baseline of 3 is appropriate and the description does not meaningfully enhance parameter understanding.

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 ('Searches') and resource ('published cross-disaster link families'), with clear filter dimensions: 'by event-type direction, optional via-event type, and optional year window.' It distinguishes from siblings by stating 'Use this when you want to discover whether a relationship family exists before you have an exact event id,' which contrasts with tools like get_disaster_links_for_event.

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 explicitly states when to use the tool: 'Use this when you want to discover whether a relationship family exists before you have an exact event id.' However, it does not explicitly name alternatives or provide 'when not to use' conditions beyond implying that having an exact event id changes the tool choice. This is clear but not fully explicit.

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