Trace funds on an EVM chain

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

Goes well beyond the readOnly/idempotent/openWorld annotations: it discloses that native and ERC-20 transfers are read, that values are converted to USD at time of transfer, that the largest recipients are expanded, and that traversal terminates at contracts and labelled addresses. It also surfaces an operational prerequisite — Ethereum works keyless via Blockscout while all other chains need ETHERSCAN_API_KEY — which is exactly the kind of environment detail annotations cannot carry.

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 the core action, then usage context, behavioral traits, chains, and the API-key caveat — a logical order with no filler sentences. The long chain enumeration is dense but earns its place by pairing with the keyless-vs-key distinction.

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 five-parameter read-only tracing tool with no output schema, the description covers inputs conceptually, chain support, credential requirements, and termination behavior. The remaining gap is the result shape — an agent is not told what the trace output looks like (e.g. a graph, per-hop lists, or USD totals) — which matters slightly more given there is no output schema.

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 only 40%, and hops, branchFactor, and sinceUnix have no descriptions in the schema. The description partially compensates by conveying the traversal model (forward following, expansion of largest recipients, stopping conditions), which gives conceptual meaning to hops and branchFactor, but it never names them and says nothing about sinceUnix as a time window.

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 — follow funds forward from an address on an EVM chain — and positions itself against siblings by naming trace_funds and follow_bridge as the tools whose output typically feeds it. It also enumerates the supported chains, so an agent can tell immediately whether the tool applies.

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 clear usage context: it is usually run on the destination address of a bridge crossing discovered by trace_funds or follow_bridge, which implicitly routes multi-chain tracing elsewhere. It does not spell out an explicit when-not-to-use case (e.g. Solana or non-EVM), though the chain list partially covers that by enumeration.

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