Check route survival

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

With no annotations provided, the description carries the full burden of behavioral disclosure, and it does so thoroughly. It discloses that blocking:true means refuse the deposit, that reasonClass distinguishes protocol_refused from no_aggregator_quote, that the probe is same-chain only, and that an unscreened vault returns screened:false with no fabricated verdict. It also states 'Read-only' at the end, which is critical behavioral information in the absence of readOnlyHint annotations.

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 dense but well-organized: it opens with the core question, then lists the return fields, then explains the blocking semantics, then the reasonClass distinction, then the same-chain limitation, then the screened:false behavior, and ends with usage guidance. Every sentence earns its place, though it is somewhat long. The front-loading of the core purpose is excellent.

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 read-only probe tool with 2 well-documented parameters and no output schema, the description is remarkably complete. It explains what the return values mean (verdict, USD in/out, fraction retained, path probed, when), what blocking:true means, what reasonClass values indicate, the same-chain scope, the screened:false edge case, and when to call it. An agent has everything needed to invoke it correctly and interpret the result.

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 schema already documents both parameters (address and chainId) with descriptions. The tool description adds context about what the vault is (a vault contract) and that chainId is the EVM chain id, but it doesn't add much beyond the schema. Baseline 3 is appropriate because the schema does the heavy lifting and the description doesn't need to compensate.

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 opens with a concrete question ('Can a deposit into this vault be exited at size, measured today?') and then states the exact resource and action: it returns a daily round-trip route screen (USDC -> position -> USDC) with verdict, USD in/out, fraction retained, path probed, and when. This clearly distinguishes it from sibling tools like get_vault_score or explain_vault_score, which are about scoring/explaining rather than probing route survival.

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 'Call this BEFORE moving money' and explains when the tool should be used. It also provides exclusion guidance: the probe is SAME-CHAIN only and says nothing about bridging in from elsewhere, so an agent knows not to use it for cross-chain checks. It also distinguishes between two failure reasons (protocol_refused vs no_aggregator_quote) and what each implies, which helps the agent decide how to act on the result.

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