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

Annotations already cover read-only and idempotent aspects. The description adds valuable behavioral context: 'fields sparse if upstream thin' warns of incomplete data, and it reaffirms no account access or order placement. No contradiction with 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?

Three concise sentences front-load the core function, then add the token alternative, read-only restriction, and disclaimers. No wasted words; efficient and well-structured.

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 the presence of an output schema and annotations, the description covers all necessary usage context: single transaction lookup, sparse-field behavior, the distinction from token tool, and safety boundaries. Nothing essential is missing for an agent to call it 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?

The input schema has 100% coverage for all four parameters, each with descriptive text. The description adds little beyond the schema for parameters; it only hints at sparse fields in the response, which is already noted in the schema for tx_hash. Baseline 3 is appropriate given high schema coverage.

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 states the tool's purpose: retrieve one transaction by hash. It distinguishes itself from the token-view tool by explicitly pointing to get_token_onchain, making it unambiguous among siblings.

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?

It provides clear guidance for when to use this tool vs. the token alternative, and reinforces its read-only nature. It does not explicitly exclude other on-chain tools like get_address_transactions, but the single-transaction scope is evident.

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