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

The description discloses the scoring methodology (complex emergencies x3, epidemics x2.5, droughts x2), the returned fields, and the update frequency ('Updates: daily'). This goes beyond the readOnlyHint annotation by providing substantive behavioral detail, without contradicting any annotations.

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 compact: two sentences deliver the core function, output fields, use cases, and update cadence with no extraneous content. It is front-loaded with the most important information about what the tool returns.

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 fully enumerates the return fields (crisis_level, trend, ongoing_count, new_30d, by_type mix, countries_affected, recent-crises list) and explains the index formula. Combined with clear use cases and update frequency, the tool is sufficiently understood for correct selection and invocation.

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 only parameter, 'days', is fully described in the input schema, including its optional nature and the Gold tier requirement. The main description adds no parameter-specific semantics, so the schema's complete coverage justifies the baseline score of 3.

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 it 'Returns a 0-100 global humanitarian-crisis load index' with a precise severity-weighting formula and lists the output fields. This makes the tool's unique function unmistakable and distinguishes it from sibling tools.

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 gives explicit usage context: 'Call when the user asks about active humanitarian emergencies, global crisis load, or disaster-response demand, or when timing NGO surge staffing, sovereign-risk reviews, or supply-chain exposure checks.' It lacks explicit when-not-to-use guidance or alternatives, but the call scenarios are clear and actionable.

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