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

With no annotations provided, the description carries the full burden of safety disclosure. It explicitly states the operation is read-only and free, which are key behavioral traits. It also lists the return fields, giving the agent a clear picture of the output without an output schema.

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 two succinct sentences, front-loaded with the primary verb and object, followed by return values and cost/safety notes. Every word adds value and there is no redundant information.

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 single-parameter, read-only query with no output schema, the description covers all essential aspects: the exact retrieval key, the returned fields, and the free/read-only nature. This is sufficient for an agent to select and invoke the tool 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 already fully describes the single parameter tx_hash as 'Base L2 transaction hash of the anchored attestation', so schema coverage is 100%. The description's phrase 'previously-anchored' reinforces the schema but does not add new semantic meaning beyond what is already provided.

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 action (fetch), the resource (a previously-anchored attestation), and the lookup method (by Base transaction hash). It is distinct from sibling tools such as zk_anchor_to_base, which creates the anchor, and zk_verify_proof, which verifies a proof.

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 establishes when to use the tool: to retrieve an attestation after it has been anchored, given its transaction hash. It does not explicitly name alternatives or exclusions, but the context is clear and the sibling tool names help differentiate use cases.

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