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

Annotations already cover safety (readOnlyHint=true, destructiveHint=false) and the description is consistent with them ('sends nothing itself'). Beyond that, it discloses real behavioral detail: the exact two-step sequence (approve gateway, then deposit), the hardcoded 0.5% minimum out, partner ID 2, the Base chain, and that the address must sign and send in order.

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?

Four sentences, each carrying unique information (availability caveat, construction, parameters/chain, non-sending guarantee), with no filler. The leading error caveat is front-loaded but slightly delays the core purpose statement.

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?

With no output schema, the description should ideally sketch the return payload (two unsigned transactions); it implies this via 'builds the two calls' but never states the response shape or any expiry/deadline. Otherwise it gives everything needed for a preparation tool: inputs, chain, sequence, and hardcoded values.

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 'address' and 'amount' are already documented in the schema. The description only alludes to 'an address' and 'deposit USDC' without adding format, units, or constraint detail, so the baseline 3 applies.

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 specific action on a specific resource: it builds the two calls that deposit USDC into Obento for an address, and explicitly notes it 'sends nothing itself.' That contrast with prepare_withdrawal is clear enough for an agent to pick the right sibling without opening a schema.

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 opening line gives an explicit when-not-to-use condition ('Deposits are closed while Obento is paused, so this returns an error'), which is genuinely actionable. It does not name an alternative tool or describe a route to take while paused, so it falls short of the 5-level routing guidance.

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