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

Annotations already declare readOnlyHint=true, openWorldHint=false, destructiveHint=false, so the safety profile is covered. The description adds the detail that the call_id parameter resolves to a full call record with five named sub-fields, which is useful context beyond annotations. But it says nothing about what happens when call_id is invalid, whether the transcript is paginated, or the data's freshness.

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?

Single sentence, front-loaded with the core purpose. The parenthetical 'who said what' is a helpful gloss on 'transcript'. No wasted words.

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 1-param read tool with no output schema, the description should specify the call_id's origin and format, and ideally reference list_calls as the source of valid IDs. The enumerated return fields partially compensate for the missing output schema, but the input side remains under-documented.

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 0% and the single parameter call_id has no description in the schema, so the description carries the burden. It doesn't state that call_id is the identifier used to select the record, nor its format (UUID vs numeric). Baseline for a 1-param tool with a high-coverage schema would be ~4, but here the schema is empty and the description does little to compensate.

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?

States a specific verb+resource ('One call in full') and enumerates what is returned (transcript, outcome, summary, objective, tool use). This clearly distinguishes it from the sibling list_calls (which would return many). However, it doesn't name list_calls as the alternative or explicitly frame itself as the single-record counterpart.

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 explicit when-to-use guidance. The phrase 'One call in full' implies it's for drilling into a single record, but the description never states when to use this versus list_calls or other search tools. The agent must infer the retrieval pattern from the name alone.

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