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

Beyond the annotations (readOnly, idempotent, non-destructive), the description details auto-detection of indicator types, queries against abuse.ch feeds per indicator, per-type source coverage, per-indicator verdict with sources_queried/sources_unavailable for partial failures, and rate limits. This is substantial behavioral context not present in annotations.

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 dense and information-rich, with each sentence serving a purpose (behavior, use case, rate limits, output). However, it is a single multi-clause block of about 5-6 sentences; while efficient, breaking it into bullets or shorter sentences would improve readability. Still, no fluff and well front-loaded.

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?

Given the tool's complexity (batch, multiple IOC types, partial failures, rate limits), the description covers source coverage per type, failure visibility, rate limits, and the summary return fields. Since an output schema exists, it needn't explain return values in depth. This is complete for an agent to use correctly.

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%, so baseline is 3. The description adds meaning by explaining per-item rate limit counting ('1 per item') and that rate limits are 'same for Free and Pro', which is not in schema. It also clarifies that auto-detection plus per-indicator feed queries happen, but some of this is already in the schema description.

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 clearly states the tool 'Batch query multiple IOCs... in 1 request' with specific supported types (IP/domain/URL/hash) and a limit of 50 per call. It explicitly contrasts with 'use ioc_lookup for single indicator', differentiating it from its sibling.

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?

Provides explicit guidance: 'Use for SOC alert triage or batch enrichment; use ioc_lookup for single indicator.' This directly tells the agent when to use this tool versus the alternative, and also mentions per-type source coverage matching ioc_lookup, setting expectations.

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