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

The annotation readOnlyHint=true already discloses the safe read nature. The description adds the behavioral context that this should be surfaced immediately in crisis situations but does not disclose additional traits like authentication or rate limits. It is consistent with the annotation, so a mid-range score is appropriate.

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, immediately states the core function, and the usage guidance is secondary. There is no wasted wording.

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 zero-parameter, read-only tool, the description is sufficient: it names the exact resources and gives the usage trigger. It doesn't describe the return format, but there is no output schema and the payload is self-evident from the listed items.

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?

There are no parameters, so the input schema is empty. The description does not need to explain parameter semantics; the baseline for 0 parameters is 4.

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 explicitly states 'Return the canonical 988 / 911 / Crisis Text Line payload,' which is a specific verb+resource. This clearly distinguishes it from sibling tools like get_article and search_articles that deal with articles and microsite info.

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?

It provides explicit when-to-use guidance: 'Surface this immediately whenever the user signals self-harm or imminent danger.' This is a clear triggering condition and, given the sibling tools are unrelated, no alternative tool is needed for crisis situations.

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