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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description complements this by adding the data source (MalwareBazaar), rate limits (Free/Pro hourly), and the return structure. It does not contradict annotations, and provides helpful operational context.

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 compact yet information-dense: source, purpose, usage guidance, companions, rate limits, and return fields are all covered in two sentences plus a struct. Every sentence serves a distinct function with no fluff or redundancy.

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?

The tool is simple (one parameter, output schema present), and the description covers the key aspects: what it queries, what it returns, when to use it, rate limits, and relationships to siblings. Nothing essential is missing for an agent to invoke it 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 description coverage is 100%, with the file_hash parameter fully described (accepted formats, character lengths, lowercase hex, example). The description adds no new parameter-level information beyond what the schema already provides, so baseline 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 clearly states the tool queries MalwareBazaar for file hashes and lists the specific return fields (malware family, file type, size, etc.). It explicitly differentiates from sibling tools like ioc_lookup by noting the alternative for auto-detection of all IOC types.

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 to check if file hash is known malware; use ioc_lookup for auto-detection of all IOC types.' It also names companion tools (threat_intel, exploit_lookup) and their distinct purposes, leaving no ambiguity about when to choose this tool.

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