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

The annotations declare readOnlyHint=false and openWorldHint=true, so the description is not repeating the safety profile; it adds real behavior such as the tri-state verdict, per-check evidence, and the fail-safe rule that missing data never yields ALLOW. It does not disclose what the non-read-only side effect actually is (state written, receipt persisted, cost, external lookups per call), which is the key gap given readOnlyHint=false.

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 short sentences, with the imperative timing rule front-loaded before the return contract. Nothing is restated from the title or the schema, and every clause carries operational meaning.

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?

With no output schema, the description carries the return-value burden and does so adequately (verdict, per-check facts, signed receipt). For a policy-driven gate it is nearly complete, though it leaves out latency/cost expectations and how it relates to gate_batch for multi-token flows.

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 documents the token address, preset names, deny_if/review_if expressions, and the unknown handling. The description adds meaning beyond that by stating the governing fail-safe semantics (missing data does not default to ALLOW unless policy says so), which is precisely what the policy's "unknown" field controls.

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 states a concrete action (evaluate a token before purchase on Robinhood Chain) and the exact output vocabulary (ALLOW, DENY, REVIEW, per-check facts, EIP-712 receipt). An agent knows immediately this is a pre-trade risk gate rather than a data lookup. It never names a sibling (e.g., gate_batch for multiple tokens), so differentiation still requires inference.

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?

"Call BEFORE buying a token" gives explicit timing guidance that selects this tool over the read-only fact and receipt siblings. It does not state when NOT to use it, nor point to gate_batch or gate_facts as the alternative for batch or lookup cases, so exclusions are left implicit.

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