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

Annotations already declare read-only, idempotent, non-destructive, open-world behavior. The description adds meaningful state semantics: the record may be pending or anchored and an associated ledger entry appears only once anchored. It does not discuss auth, rate limits, or not-found behavior, so it is not a 5.

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?

Two compact sentences, front-loaded with purpose and with no filler. The Resume pointer is placed after the primary return behavior, preserving clarity.

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 one-parameter read with an output schema, the definition covers what is returned, the pending/anchored distinction, and the list-view alternative. No critical calling information 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?

Schema coverage is 100% and the schema already defines sha256 as a 64-hex canonical SHA-256. The description reinforces 'canonical SHA-256' but adds no parameter format, constraints, or alternative input semantics beyond the schema, so baseline 3 applies.

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 names a specific verb ('Return') and resource ('one agreement record'), ties lookup to canonical SHA-256, and points to nenrin_resume as the list view. It lets an agent distinguish single-record retrieval from list retrieval.

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 gives clear context for using this tool when a canonical SHA-256 is known and identifies nenrin_resume for listing anchored agreements. It stops short of explicit when-not guidance or naming nenrin_ledger_entry as a related alternative.

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