fetch-chunk

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, which the description aligns with. Beyond this, the parameter description for cacheKey adds behavioral detail: 'Cache expires after 10 minutes', which is not covered by annotations. No contradictions.

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 the core purpose, and contains no extraneous words. Every sentence earns its place, making it highly efficient for an AI agent to parse quickly.

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, combined with detailed schema and annotations, covers the tool's purpose, usage, and parameter constraints. However, since there is no output schema, the description could have briefly noted the structure of the returned chunk (e.g., 'returns the chunk data or an error'). This minor gap prevents a perfect score.

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 both cacheKey and chunkIndex fully described in the input schema. The tool description does not add further meaning beyond what the schema provides, so a baseline score of 3 is appropriate.

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 'Retrieves cached chunks from a changeMode response', clearly identifying the verb (retrieves) and resource (cached chunks). The specificity of 'changeMode response' distinguishes it from sibling tools like web-search or analyze-media, which serve different purposes.

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 advises to 'Use this to get subsequent chunks after receiving a partial changeMode response', directly stating when to employ the tool. While it doesn't explicitly mention when not to use it or list alternatives, the context is clear and sufficient for an agent to decide.

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