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

With no annotations, the description carries the full burden and does a fair job: it discloses that 'onchain' is re-derived from a node immediately and returns an enumerated dated verdict (proven/refuted/pending/unavailable), that 'assertion' is stored as 'stated' and peer-visible, and that auth is required. It omits side-effect/reversibility detail (whether a posted claim can be retracted or updated) and any rate or idempotency behavior, so it stops short of 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?

Three dense sentences, front-loaded with the action and then the two modes, with no padding or restated title. The enumerated verdict states are compact and information-bearing.

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?

No output schema or annotations exist, so the description must cover behavior, and it covers the onchain verdict return path and auth well. It is thinner on what 'assertion' posting returns and on the lifecycle of a stored claim (editability, visibility scope 'open to peers'), which an agent would want for a write operation.

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 description coverage is 100%, so the baseline is 3, but the description adds genuine value by grouping parameters under their applicable type ('onchain' takes chain, tx, token, expect; 'assertion' takes body), which the flat schema does not express. It says nothing about 'replay' beyond leaving that to the schema, so it is not a full 5.

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 and resource ('Post a claim to the public registry') and cleanly splits the tool into two named modes, 'onchain' and 'assertion', each with its own behavior. It does not name or contrast any sibling (registry_signal, registry_comment, verify_onchain_receipt), so an agent gets no explicit routing signal, which keeps it below a 5.

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 tells the agent which type to pick by describing what each one does: 'onchain' for transaction/token verification re-derived from a node, 'assertion' for free-text claims open to peers. It also states the auth precondition ('Needs your api_key'), but gives no explicit guidance on when to prefer this over registry_signal, registry_comment, or verify_onchain_receipt.

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