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

Annotations already provide readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds context about the scope ('from the connected account') and the return ('full apicall record'), which is useful but does not go beyond what annotations imply. No contradictions with annotations, and the added details are minor.

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 with no wasted words. The primary action is front-loaded, followed by the requirement and a clear alternative. Every sentence contributes meaning, and the structure is optimal for quick scanning by an agent.

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 get-by-ID tool with one parameter, no output schema, and annotations covering safety, the description is complete. It covers what the tool does, when to use it, where the ID comes from, and what it returns. Nothing an agent needs to invoke it correctly is missing.

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?

The schema already fully describes the `id` parameter (100% coverage). The description adds value by specifying that the ID is obtained from `list_unified_apicalls`, which is a source hint beyond the schema's generic description. This extra context helps the agent understand where the value comes from, so it earns a score above the baseline of 3.

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 ('Retrieve') and resource ('single apicall by its ID'), and explicitly distinguishes itself from the sibling `list_unified_apicalls` by noting it retrieves a single record rather than searching or listing. This makes it immediately clear what the tool does and how it differs from alternatives.

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 when to use this tool ('Use when you already have the ID') and when not to ('to search or list apicalls, use `list_unified_apicalls`'), naming the alternative directly. It also tells the agent where to obtain the required `id` (from `list_unified_apicalls`), leaving no ambiguity about usage context.

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