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

Annotations establish that this is a non-read-only, non-idempotent, non-destructive write; the description adds two things they don't: that it is non-custodial and never moves money (important given submit_payment_tx exists) and that the note will be public. It still doesn't say what the side effect is on the trade or warn that retries aren't safe.

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 clauses, all load-bearing: role, action plus optional field, then the two constraints (non-custodial, auth). Zero filler and the key facts are 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 small mutation tool with no output schema and annotations already carrying the safety profile, the description covers the essentials: who may call it, auth requirement, and the non-custodial guarantee. Missing only the meaning of trade_id and the expected state transition after delivery.

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 0%, so the description is the only place parameter meaning can come from. It usefully explains that note is optional and publicly visible, but trade_id is never described, and "current step" conflicts with a parameter that identifies a trade rather than a step.

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?

Names a specific verb and resource ("mark the current step delivered") and scopes it to the Seller role, which separates it from buyer-side siblings like confirm_delivery. It stops short of naming the sibling it is not, and "current step" is vague about which step is meant given the only identifier passed is trade_id.

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 role gate ("Seller:") tells the agent who may call it, which is real routing guidance for a two-sided trade flow. However, it never states when to use this versus confirm_delivery, nor any prerequisite such as an open trade or a prior step having been completed.

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