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

With no annotations, the description carries the full behavioral burden and does so richly: verdict semantics, the rule that a confirmed-bad listing forces 'malicious', the scanner/Tor exception for GreyNoise-identified benign research scanners, the 'unknown' condition, GreyNoise's keyless 25-lookup/week server-wide quota and its failure handling, hostname resolution behavior, and the read-only safety profile. This is far more than the schema or any annotation would provide.

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?

Long but dense and front-loaded: the aggregate verdict comes first, then the decision rules, then the failure mode. Each sentence carries information, though the single-paragraph block is heavy and could be more scannable, keeping it just under a 5.

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 tool with no output schema and no annotations, the description compensates fully — it describes the return content (verdict, which signals fired, which sources answered or failed), the degradation path when GreyNoise is unavailable, and the safety profile. Nothing an agent needs to invoke or interpret it is missing.

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 there is only one parameter, so the baseline is 3. The description adds meaning beyond the schema by specifying the resolution policy for a host name ('the first resolved IP is used'), which the schema's example does not state.

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 ('Fold every keyless IP-reputation source into one verdict') and enumerates exactly which sibling checks are subsumed (ip_blocklist_check, ip_reputation, feodo_c2_check, tor_exit_check, dshield_ip_check). An agent can distinguish this aggregate from the individual checks without opening any schema.

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?

Clearly conveys the context in which this tool is the right call — when a single consolidated verdict is wanted instead of the five underlying lookups, which it names. It stops short of an explicit directive ('use this rather than calling ip_blocklist_check directly') or any when-not-to-use exclusion, so it falls short of a 5.

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