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

Beyond the annotations it discloses the credit cost (1 Creative Credit), a per-connection daily spend cap, that the call blocks for roughly two minutes rather than returning a job handle, and that the idempotency key should be reused after a timeout. That is exactly the operational context an agent needs before issuing a billable, long-running write.

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?

Short and mostly front-loaded on cost and the required key, with the sibling routing at the end. The first clause is syntactically broken, which wastes one of the few sentences available.

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 billable generation tool with no output schema, it covers cost, blocking duration, idempotency and the correct alternative tool for ads. It does not describe what a returned pack contains or how large it is, which is a minor gap given there is no output schema.

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 71%, so most parameters are already documented, including expected_credit_cost and idempotency_key. The description reinforces the required pairing of credits and key but adds little that the schema does not already say, and it says nothing about brand_id, platform, persona_id or brief.

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 concrete verb and resource (write a social copy pack) and explicitly distinguishes it from siblings: pricing comes from quote_content_pack and ads belong to create_visual. The opening sentence is garbled ('Write the pack quote_content_pack priced'), which costs a little clarity, but the intent is still recoverable.

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 gives real when-to-use routing: use create_visual for ads, do not poll get_job after calling, and supply expected_credit_cost from quote_content_pack. It stops short of an explicit 'call quote_content_pack first' instruction and says nothing about when not to generate a pack at all.

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