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

Annotations already cover readOnly, idempotent, and non-destructive semantics, so the bar is lower. The description still adds real behavioral context beyond them: 'cached' signals it only returns existing translations and will not generate new ones, and 'No paid work is created' conveys a cost/authorization trait the annotations do not express.

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?

Two short sentences, no filler, and the core purpose plus the cost constraint are front-loaded. Every sentence earns its place.

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 4-parameter read tool with zero schema descriptions and no output schema, the definition is too thin. It never explains target_language filtering, pagination via limit/cursor, or what happens when no cached translation exists, so an agent lacks enough to invoke it confidently.

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 0% and there are 4 parameters. The phrase 'for a call' loosely maps to call_id, but target_language, limit, and cursor are entirely unexplained in both the schema and the description, leaving key filtering and pagination semantics undocumented.

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 states a specific verb and resource: 'Read cached machine translations for a call.' The phrases 'cached' and 'No paid work is created' implicitly distinguish it from the sibling request_call_translation tool, but no sibling is named explicitly, which keeps it short of a 5.

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?

'No paid work is created' hints at when to prefer this over a generation/request tool, but the description never explicitly names the alternative or states the condition (e.g., 'use request_call_translation if no cached translation exists'). Usage is implied, not spelled out.

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