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

With no annotations provided, the description carries the full burden of behavioral disclosure. It covers important behavioral context: the lookup is read-only, returns multiple intelligence categories, uses daily-refreshed lists, and produces an explainable risk score. This gives the agent a solid mental model, though it could mention limitations like missing data or unrestricted IP handling.

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?

The description is a single, tight sentence that packs useful detail without a wasted word. It front-loads the core action, then efficiently enumerates the value-add results. This is appropriately sized for the tool's simplicity.

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 single-parameter lookup tool with no output schema, the description supplies enough context about what it returns and why the data is trustworthy. It does not spell out error behavior or the exact output shape, but for a simple non-destructive lookup the given coverage is largely sufficient.

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?

The input schema has full description coverage for the single 'ip' parameter, so the schema already documents that IPv4/IPv6 addresses are accepted. The description adds no new parameter-level detail beyond restating that it supports both IP formats; the baseline of 3 is appropriate.

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 uses a specific action verb ('Look up') and a clear resource ('IPv4/IPv6 address'), then enumerates exactly what the tool returns: country, ASN, hosting/ISP classification, VPN/proxy/Tor/datacenter flags, and risk score. This is easily distinguishable from sibling tools named preflight_context and read_page_preview, which are clearly about other concerns.

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 implies the use case — when you need IP enrichment or risk intelligence for an address — but it does not explicitly state when to prefer this tool over alternatives or when not to use it. No exclusions or comparisons are provided, so the guidance is implicit rather than direct.

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