agent_card_history

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

With no annotations, the description does carry the safety burden: 'writes nothing' declares read-only and 'without trusting the register' conveys the trust model, which are genuinely useful. It omits what happens for a domain with no sealed card, any auth requirements, and whether the history is paginated or ordered, which matters for a fully unannotated tool.

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?

A single front-loaded sentence that names the resource first, then the return contents, then the trust property. Every clause adds information; only the 'what changed' and proof clauses are slightly dense.

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 tool without annotations or an output schema, the description does reasonably well by describing the returned fields. It still lacks domain formatting, ordering/pagination, and empty-history behavior, so an agent knows what it gets but not the edge cases.

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?

There is one parameter at 0% schema description coverage, so the description must compensate. It implies the domain identifies whose card history is returned but never states the expected format (bare hostname vs. URL), nor whether a lookup of an unknown domain errors or returns an empty history.

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 concrete resource (every sealed version of a domain's agent card) and enumerates the payload: capture time, listed skills, diffs, receipts, and Merkle proofs. It clearly contrasts with the write-side sibling seal_agent_card via 'writes nothing', though it never names an alternative outright.

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?

Usage is implied: auditing a card's evolution and verifying history without trusting the register. There is no explicit when-to-use, when-not-to-use, or named alternative (e.g., get_agent_passport for the current state vs. this for history), which leaves the agent to infer the routing across ten siblings.

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