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

Goes well beyond the annotations by disclosing the approval flow (exact approval of the route's spender), the fee stack (LI.FI 0.25% + Panda 0.15% plus route costs, all returned), that nothing is broadcast, and the exact return shape (ordered unsigned txs, EIP-5792 batch, simulated, sign_url for the owner). With readOnlyHint already covering safety, this is substantial added context.

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?

Front-loads the action and supported assets, then layers route, fees, direction, and return behavior in a tight sequence with no filler. It is dense and slightly long for one paragraph, but every clause carries information an agent needs.

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 7-parameter builder with no output schema, the description covers the critical unknowns: directionality limit, fee composition, approval step, non-broadcast behavior, and the returned transaction format. Nothing essential to correct invocation is missing.

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 100%, so the schema already documents all seven parameters including the defaults for to_token and to_wallet. The description restates the token and chain vocabularies but adds no syntax or constraint detail beyond the schema, matching the baseline for full-coverage schemas.

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 and resource ('Send USDC, WETH, ETH or any token from Base to another chain') and enumerates the supported destinations, so the agent knows exactly what the tool does. It is clearly distinguishable from sibling builders like build_swap by its cross-chain scope and explicit 'From Base only' framing.

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?

Gives a clear directional rule: bridging out of Base is this tool, while 'a bridge into Base starts on the other chain' — an implicit when-not. However, no sibling alternative is named (e.g., build_swap for same-chain swaps), so the routing guidance is context-rich but not fully exhaustive.

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