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

With no annotations provided, the description carries the burden of disclosing behavioral traits. It explicitly states the tool is public and requires no authentication, and it enumerates the return fields (anchor record, chain link validity, event type, sequence number, verify URL). This gives agents a clear idea of what to expect, though it does not describe failure cases or behavior for invalid hashes.

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 a single sentence that efficiently packs all necessary information: the input format, the action, the return fields, and the authentication status. There is no redundant fluff; every phrase earns its place, and the most important information (input and action) is front-loaded.

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 tool's simplicity (one parameter, no output schema), the description is quite complete: it lists all major return components and the auth requirement. However, it lacks details on potential error behavior or the exact structure of the 'anchor record,' which would be helpful given there is no output schema. Still, it is sufficiently complete for a straightforward verification tool.

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 provides 100% coverage for the single parameter, including the pattern and description. The tool description repeats the same information ('SHA-256 anchor hash (64 hex chars)') without adding new semantic meaning. Since the schema does the heavy lifting, the description adds no additional parameter-level value.

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 function: given a SHA-256 anchor hash, it returns the anchor record, chain link validity, event type, sequence number, and verify URL. The verb 'return' and the specific resource 'anchor record' make the purpose unambiguous, and the mention of chain link validity distinguishes it from sibling tools like get_chain_health or anchor_event.

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 provides clear usage context: it is used when you have a SHA-256 anchor hash and need verification details. It also notes that the tool is public with no authentication required, which is useful guidance. However, it does not explicitly mention alternatives or when not to use this tool, so it falls short of a 5.

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