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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so the safety profile is fully covered and 'Read-only' merely repeats it. The description does add useful substance by specifying what the response contains (per-participant AML risk, labels, verdict), but says nothing about auth, cost, latency, or what happens when a hash is unknown.

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?

Front-loaded with the core action, then output contents, then the focus_address hint. Efficient overall, though the trailing 'Read-only.' duplicates readOnlyHint and earns no new information.

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 usefully compensates by naming the returned artifacts (movements, participants, labels, risk, verdict). Combined with a fully documented 4-param schema and rich annotations, an agent has enough to call it correctly; only failure/edge-case behavior is unaddressed.

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 all four parameters are already documented, including focus_address scoping the verdict. The description's example ('your own deposit address') and 'from that wallet's point of view' add only marginal clarification over the schema wording, so the 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?

States a specific verb and resource ('Screen one transaction by hash') and then enumerates the payload the agent gets back: movements, participants, labels, AML risk, overall verdict. This is clearly distinguishable from sibling screen_address, which operates on an address rather than a tx.

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 one concrete usage cue for focus_address ('e.g. your own deposit address... to get the verdict from that wallet's point of view'), which is genuinely helpful. But it never says when to prefer this over screen_address or trace_funds, and offers no prerequisites or exclusions, so usage is only partially implied.

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