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

No annotations are provided, so the description carries the full behavioral burden: it usefully discloses partial-update semantics and that the operation is free (credit cost is a real concern in this platform, cf. get_balance/get_credit_usage tools). However, it says nothing about permission requirements, whether changes are reversible, or whether altering voice gender/face affects in-flight calls or existing audio.

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?

Three short sentences: fields first, semantics second, alternative routing third, with zero filler. Every clause earns its place and the most decision-relevant information is front-loaded.

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 6-parameter mutation tool with no annotations and no output schema, the description covers the editable surface, partial-update behavior, cost, and sibling routing. It lacks failure/validation behavior and permission context, which keeps it short of a 5.

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 only 33% (only id and avatar_preset are documented), so the description must compensate — and it does, mapping 'purpose' to direction, 'gender' to voice gender, and 'avatar_preset' to preset face in plain terms. The enum values themselves (male/female, sales/support/info) are carried by the schema, which is appropriate.

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 names the exact editable fields (name, description, purpose, gender, preset face) and explicitly routes company and contact edits to their own sibling tools, so an agent can separate it from set_agent_company and set_agent_contact_channels. It doesn't draw a boundary against set_agent_voice or set_agent_avatar_from_url, which overlap with 'voice gender' and 'preset face', so sibling differentiation is incomplete.

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?

'Only the fields you pass change' establishes clear PATCH semantics for when to use it, and the two explicit redirects tell the agent when NOT to use it. The remaining overlap with set_agent_voice/set_agent_avatar_from_url is left unaddressed, so the guidance is strong but not exhaustive.

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