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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is clear. The description adds useful behavioral context by naming the response components (voice_settings and platform_tools), which helps the agent understand what data will be returned beyond a generic success indication.

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 wasted words. The core operation is front-loaded, and the response detail follows naturally without redundancy.

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?

Given one parameter, read-only annotations, and no output schema, the description is largely complete: it covers purpose, input method (by ID), and key response fields. Minor omissions like error behavior or format examples are acceptable here.

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%, so the description must carry the burden of explaining the single parameter. It does so indirectly by saying 'by ID', but it does not specify the format or expected value of assistantId, leaving a gap.

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 uses a specific verb (fetch) and resource (assistant's full configuration) and clarifies the lookup is by ID, which implicitly distinguishes it from assistants_list. It lacks an explicit callout of the sibling tool, but the purpose is unambiguous.

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 phrase 'by ID' implies when to use this tool (when you have an assistant ID), but there is no explicit guidance on when to choose this over assistants_list or other sibling tools, nor any mention of preconditions.

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