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

Annotations already declare read-only, idempotent, non-destructive, open-world behavior; the description goes well beyond by disclosing the data path (own warehouse first, then a budgeted live provider), the deliberately partial registry, the `truncated: true` lower-bound semantics, and the three distinct outcomes. That is exactly the caveat context an agent needs to report results without overclaiming.

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-loaded with purpose and only mildly repetitive in restating the coverage caveat twice. Every sentence, including the outcomes list and the truncation note, carries operational meaning, so the length is largely earned.

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 nonetheless specifies payload contents, the coverage caveat shipped with results, the truncation flag, and scope limits. An agent has enough to call it and to restate the result correctly.

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% and the parameter is already typed and described, so the schema carries most of the load. The description still adds real meaning by stating that a base58 Solana address yields an out-of-scope answer rather than a clear one, which changes how the argument's failure mode is interpreted.

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 first sentence names a specific verb (trace) and resource (cross-chain bridge transfers) and enumerates exactly what comes back: bridge contract, destination chain, amount, transaction hash. Nothing about it can be confused with cex_attribution, wallet_score, or ofac_check.

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?

Explains when a result is meaningful versus a bounded negative and when nothing may be inferred, and sets a hard scope boundary (EVM only, Solana out of scope). It stops short of naming which sibling to use instead for related questions, so routing is implied rather than explicit.

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