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

No annotations are provided, so the description carries the full behavioral burden. It discloses that the tool lists anchors with specific fields, notes an unconfirmed anchor reports itself as not yet in a block, explains that a calendar-claimed height is checkable with the proof file, and states "Credential: none" and "Cost: Free." It does not explicitly confirm read-only status or pagination behavior, but the read/list behavior is clear.

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 purpose, though the first-person opening ("I want to know...") is awkward and less direct than an imperative statement. The field list and caveats are dense but each sentence contributes useful information, and the credential/cost/source metadata is appended cleanly.

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?

Because there is no output schema, the description must explain return values, and it does so thoroughly: root, entry range, entry count, construction method, Cardano transaction, write location, and OpenTimestamps proof state. It also covers the edge case of anchors not yet in a block and the provenance of calendar-claimed heights, while specifying credential, cost, and source. This is complete for a zero-parameter listing 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 tool has zero parameters and schema coverage is 100% (empty object), so the rubric baseline is 4. There are no parameters for the description to explain, and it appropriately adds no parameter semantics.

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?

States a specific verb ("Lists") and resource ("each anchor") and details the returned fields (root, entry range, construction, Cardano transaction, OpenTimestamps proof state). It clearly identifies the tool's scope, but does not differentiate itself from sibling anchor tools like check_anchor or read_anchor_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 opening "I want to know when the Court wrote its register into Cardano" suggests a use case, but there is no explicit when-to-use guidance, no exclusion conditions, and no mention of alternatives such as check_anchor or read_anchor_proof. An agent is left to infer when this listing tool is appropriate.

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