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

Annotations already declare readOnlyHint=true and idempotentHint=true, so safety is covered. The description adds the requirement for a connected account, which goes beyond annotations, and notes it fetches a 'full transcript' implying a potentially large payload. However, it doesn't elaborate on performance or error behavior. With annotations carrying the safety profile, this adds modest value, so a 3 is appropriate.

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 sentences with zero fluff. The verb and resource are front-loaded, and the auth requirement is placed at the end as a concise precondition. Every word 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 simple fetch tool with two params, an enum, and an output schema (which covers return values), the description is nearly complete. It covers what the tool returns (full transcript/detail), how to identify the target (id), and the auth prerequisite. It doesn't mention error scenarios or timeouts, but these are minor gaps given the output schema and simplicity.

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 50% – only 'id' has a description ('The callId or chatId from get_call_chat_history'), while 'channel' only has an enum. The description says 'for one call or chat' which clarifies that 'channel' distinguishes between the two, and 'by id' aligns with the id schema. It adds some context beyond the schema but doesn't fully compensate for the missing channel description, so it meets the baseline.

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 verb 'Fetches' and the resource 'full transcript and detail for one call or chat, by id.' It distinguishes this from the sibling 'get_call_chat_history' by focusing on a single item via id, making the purpose unmistakable.

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?

It provides clear context: you need an id from history ('by id') and a connected account is required. While it doesn't explicitly name alternatives or say 'use when you have an id', the structure implies this tool is for retrieving a specific record after listing, and the auth requirement is a useful precondition. No exclusions or alternative-routing are given, so it's not a 5.

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