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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, and the description adds 'Read-only; metered on your key. Needs your API key.' It also discloses the exact return fields and the per-chain variations. No contradiction with annotations. Slight deduction because the description repeats 'Read-only' that annotations already state, but the metering and auth details go beyond 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?

Every sentence earns its place: purpose, status enum, chain-specific fields, usage instruction, exclusions, return format, and operational notes (metering, API key). It is front-loaded with the core purpose and structured clearly, with no redundant or filler content.

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 tool with no output schema, the description fully compensates by enumerating all return fields and their chain variants. It covers usage, exclusions, auth requirements, and metering, leaving no ambiguity for an agent to call it correctly. The complexity is moderate, but the description addresses all practical needs.

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% – both parameters (hash and chain) are fully documented in the schema, including the format for hash (0x… for EVM, base58 for Solana) and an example chain slug. The description adds no additional parameter-specific information beyond what the schema already provides, so baseline 3 is appropriate.

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 precisely what the tool does: reports the status of a single transaction hash across chains, enumerating the possible statuses and the chain-specific details returned. It explicitly names sibling tools it is not (get_history for address transfers, decode_calldata for decoding), making its purpose unambiguous.

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 direct, actionable guidance: 'Use it to poll a transaction you sent or were told about' and explicitly states what it is NOT for, naming the two alternative tools. This is a textbook example of when-to-use/when-not-to-use clarity.

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