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

No annotations are provided, so the description must disclose behaviors. It mentions refusal of non-created offers and 'custom_fields-only surface', which are useful. However, it lacks detail on side effects, authorization, or what happens after a successful patch.

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 a single sentence that covers the core purpose and a key constraint. It is concise and front-loaded, though it could include more structured detail without sacrificing brevity.

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?

Despite 6 parameters and no output schema, the description omits return value, validation behavior, and the role of the 'dry_run' parameter. For a mutation tool, this leaves gaps in understanding the complete behavior.

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 100%, so the input schema already explains all parameters. The description adds 'custom_fields-only surface', reinforcing the intent but not adding new parameter-level meaning beyond the schema.

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 tool patches draft-offer custom fields, specifies the scope (draft offers only), and distinguishes from siblings like patch_offer_compensation or patch_offer_core by focusing on custom fields.

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 says 'Refuses non-created offers', which guides when not to use it. It also implies usage for draft offers. However, it does not explicitly contrast with alternative patch tools or provide complete when-to-use/not-to-use guidance.

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