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

Beyond the readOnlyHint annotation, the description discloses the data source (GDELT), methodology (daily composite z-score), update frequency (daily), and the Gold tier requirement for historical series. This adds valuable behavioral context about access and data composition.

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 and information-dense: two well-structured sentences that front-load the core return and then explain usage. Every sentence contributes purpose, methodology, or use-case context without 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?

The description covers the tool's output, methodology, update cadence, access tier, and use cases. Even without an output schema, the listed return components (trend, percentile, top_drivers, lineage) give a complete picture. The single parameter is well-documented, and annotations cover safety.

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 single optional parameter 'days' is fully documented in the schema with a clear description, and schema coverage is 100%. The tool description does not add additional semantics about parameters beyond what the schema already provides, so the baseline of 3 applies.

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 returns a 0-100 global stability score for the world news climate, with methodology and specifics (GDELT event tone, conflict-event share, since 1993). This is a specific verb+resource combination that distinguishes it from siblings.

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 explicit when-to-use guidance: 'Call when the user asks about geopolitical risk, global instability, conflict escalation, international tensions, unrest, or the news climate...' It covers a comprehensive set of triggers but does not mention alternatives or when not to use, so it slightly misses the full 5 criterion.

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