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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the agent knows this is a safe read operation. The description adds context about the content topics covered, enriching what the tool returns beyond the annotation basics, without contradicting them.

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 two sentences, front-loaded with the purpose and example topics. It is concise and every sentence adds value, wasting no words.

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 simplicity, the safe annotations, and full schema coverage, the description is adequate. It does not describe the output structure (no output schema exists), but the nature of the tool—a list of principles—is implied by the examples. It could briefly mention how the 'format' parameter affects output, but the schema covers that. This is complete enough for a simple read operation.

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% for both parameters, with detailed descriptions for 'context' and 'format' already present. The tool description adds little new meaning—it mentions filtering by context but does not elaborate beyond the schema. Baseline 3 applies because the schema fully documents parameters.

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 retrieves UX-writing principles and lists specific topics (clarity, active voice, error-message anatomy, etc.), which differentiates it from siblings like get_principles or get_brand_principles. The verb 'get' and resource 'UX-writing principles' are specific and non-tautological.

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 description implies when to use the tool by offering a filter by writing context (e.g., 'error messages'), making it clear the tool is for obtaining writing guidance. However, it does not explicitly state when not to use it or mention alternatives such as get_content_pattern, so there is some room for ambiguity.

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