PeerGlass

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

Adds valuable behavioral details beyond annotations: notes parallel execution ('All queries run in parallel for fast results'), lists specific blocklist providers included in the check, and describes the return value format ('Per-list listed/clean status with return codes'). Does not mention rate limits or error behaviors, but covers execution model well.

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?

Well-structured with front-loaded purpose statement, followed by behavioral details (parallel execution), then explicit Args and Returns sections. Every sentence adds value. Minor deduction because the Args section duplicates information that belongs in schema (though schema coverage is reported as inadequate).

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?

Adequately complete for a read-only lookup tool: combines rich annotations (idempotent, readOnly, openWorld) with description coverage of inputs, outputs, and execution behavior. Given the presence of output schema documentation in the description and the simple single-input nature, no critical gaps exist.

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?

Compensates effectively for 0% schema description coverage at the root level by documenting both nested parameters (ip, response_format) in the Args section, including the default value ('markdown') and valid options for response_format. Provides redundant example for ip that schema also contains, but ensures clarity.

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?

Excellent specificity: states the exact action ('Check'), resource ('IPv4 address'), and scope ('30 DNS blocklists' including named lists like Spamhaus ZEN, Barracuda, SORBS). The mention of specific blocklists distinguishes it from generic threat intel or DNS resolution tools in the sibling list.

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 implicit usage context by specifying the domain (DNS blocklists/RBLs for spam/security), but lacks explicit guidance on when to use this versus siblings like peerglass_threat_intel or peerglass_dns_censorship. No explicit prerequisites or exclusions listed.

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