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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is covered. The description adds only the recency scoping and the result field list, which the output schema already carries; it discloses no pagination, ordering, or rate-limit behavior. No contradiction with 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?

A single front-loaded sentence with no filler; the scope qualifier comes before the field list. It is appropriately sized for a simple list tool, though the trailing field enumeration is largely redundant with the output schema.

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 read-only list tool with an output schema (so return values need no explanation) and full annotation coverage, the description is minimally adequate. It falls short on parameter behavior and on distinguishing itself from the several overlapping YARA/threat siblings.

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 0% and the description never names or explains the two parameters. 'Last hours' loosely hints at the hours parameter but gives no units, default, or behavior when omitted, and the limit parameter (default 20) is entirely unaddressed.

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 states a specific verb+resource (list YARA rule matches) plus a scope qualifier (scans in the last hours) and enumerates the returned fields. It is clear on its own, but it never differentiates itself from near-identical siblings such as get_yara_by_scan, get_yara_matches, get_recent_threats, or get_yara_stats.

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 'scans in the last hours' window implies a recency/monitoring use case, which is weak implicit guidance for when to pick this over the per-scope alternatives. No explicit when-to-use, when-not-to-use, or named alternative appears.

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