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

Annotations already establish a safe read (readOnlyHint, idempotentHint, destructiveHint=false), so the bar is lower. The description earns credit by disclosing that only the *active* revision is returned (older revisions are not), that content is human-authored verbatim text, and that this resource is immutable via the assistant.

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?

Two short sentences, zero filler, with the returned scope ('active revision') front-loaded before the read-only constraint. Nothing restates the title or repeats schema content.

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?

No output schema exists, so the description carries the return-value burden; it conveys the semantic content (the rule's requirements text) but not the shape of the returned object (revision id, timestamps, requirement fields). Adequate for a one-parameter getter, but leaves the response format to inference.

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?

Single parameter with 100% schema description coverage, so the schema already explains rule_id and its lineage semantics. The description adds nothing about the identifier format or sourcing; baseline 3 applies when the schema does the work.

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 names the resource precisely and adds scope detail: it returns the 'active revision' of a rule, specifically the requirement text in the owner's own words. That distinguishes it from history/revision siblings and from finding/site getters, though no verb is stated ('Get rule' must supply that framing).

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?

Usage is only implied: the schema note that rule_id is 'the rule id a finding names' hints this is called after reading a finding, and 'Rules cannot be changed through an assistant' implies a lookup-only workflow. No explicit when-to-use, prerequisites, or named alternatives are given.

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