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

Beyond the readOnly/idempotent/openWorld annotations, the description discloses important behaviors: contract creation is flagged via null to, pending transactions via null block, and unknown hashes return found:false rather than an error. It also explains access/pricing behavior, such as the x-credit-token header and free daily calls.

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 front-loaded with the core purpose and does not waste words on fluff. It is longer than strictly necessary, but the extra details about special cases, unknown-hash behavior, and access requirements all serve the agent's correct invocation.

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?

Given a single documented parameter and the presence of an output schema, this description is complete for invocation: it covers the purpose, special-case flags, error/unknown behavior, and how to authenticate/cost. No critical operational detail 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?

The schema already fully documents the only parameter (hash) with 100% coverage, so the baseline is 3. The description adds 'Required input: hash' but does not meaningfully extend the parameter's semantic meaning beyond what the schema states.

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 clearly identifies the tool as returning a raw, unedited Base transaction by hash, listing the specific fields returned. It differentiates from likely siblings such as base_receipt, base_block, tx_decode, and ai_tx_explain by emphasizing 'exactly as the chain has it' and 'unedited.'

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 makes the use case clear: retrieve a raw transaction by hash when you need the chain-level fields. It does not explicitly name alternatives or state when not to use it, but the raw-transaction framing gives clear context relative to sibling tools.

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