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

Annotations provide readOnlyHint=true, but the description adds substantial behavioral context: items are relevance-scored and ranked by momentum, local-language press is translated to English, and the output includes titles, sources, and links. This goes well beyond the annotation to explain how the tool behaves and what the user receives.

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 three sentences, front-loading the core purpose, then covering translation and return details. Every sentence contributes distinct information with 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?

With a readOnly hint, a present output schema, and full parameter schema coverage, the description still adds value by explaining the signal's nature (relevance-scored, momentum-ranked), translation of local press, and return fields. It also addresses the relationship to a sibling tool, making it complete for the tool's complexity.

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 coverage is 100% with descriptions for both region (enum) and limit (default/cap). The description adds little beyond the schema—only reiterating the region values and noting that get_china_signal is a preset, which doesn't materially enhance parameter meaning. Baseline 3 is appropriate given the high schema coverage.

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 retrieves the current AI signal for a region, enumerates the valid regions (china, korea, japan, eu), and describes the content (recent, relevance-scored items ranked by momentum) along with the return format (titles, sources, links). It distinguishes itself from the sibling get_china_signal by positioning itself as the canonical regional tool with get_china_signal as a preset.

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 it is 'the canonical regional tool' and calls out get_china_signal as a preset for region 'china', directly informing the agent when to use this tool versus an alternative. While it doesn't compare against every sibling, the guidance is clear and actionable for regional signal needs.

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