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

Annotations only declare readOnlyHint=false, but the description adds substantive behavior: it is a state-changing write, it is 'not safe to repeat blindly' (non-idempotent caution), and crucially that orders already placed are unaffected. This is exactly the non-obvious context an agent needs beyond the annotation.

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, front-loaded with the role and action, then the write warning. The color in 'cannot unmake a commission somebody already funded' is slightly verbose but does carry the concrete point that existing orders survive.

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 two-parameter mutation with no output schema and thin annotations, the description covers role, write semantics, idempotency risk, and side-effect scope. Missing only error/edge behavior (e.g., invalid or already-withdrawn offer) and whether the action is reversible.

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 50%: 'reason' is documented ('3 to 1000 characters, published') while 'offer_id' has no schema description. The description reinforces that the reason is public, but adds nothing about the offer_id format or validation. Baseline 3 is appropriate given partial coverage.

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?

States a specific verb+resource ('withdraw' an 'offer') and scopes it with the role constraint 'Seller only'. The phrase 'stop taking orders on your offer' distinguishes it from the sibling withdraw_listing and the generic withdraw, since the effect is on an advertisement that receives orders.

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 'Seller only' precondition tells the agent who may invoke it, and the effect statement implies the intent (cease accepting new orders). However, no alternatives are named (e.g., withdraw_listing, order_offer, publish_offer) and there is no explicit when-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.