get_principles

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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive behavior, so the safety profile is covered. The description adds useful behavioral context by detailing the content delivered and noting results are 'matched to' the design context, suggesting selection/filtering behavior.

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 a single tight sentence that front-loads the purpose before enumerating the returned principle types. Every phrase earns its place: no filler, no repetition, and no redundant restatement of the tool's name.

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 description, combined with a fully-documented schema and safe-read annotations, gives an agent enough to select and invoke the tool. It lacks an explicit statement about the platform/category substitutions, but those are fully captured in the schema descriptions, so this is not a material gap.

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%, so descriptions already define context, format, category, and platform adequately. The description's first sentence reinforces the 'context' parameter concept but does not need to add more; baseline 3 is appropriate given high coverage.

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 a specific verb and resource: 'Get design principles' for a UI context, and enumerates the types of content returned (heuristics, UX laws, Gestalt, accessibility, typography, color). This distinguishes it from sibling tools like get_content_principles or get_brand_principles, whose scopes differ.

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 clearly establishes when to use the tool: for a UI context, matched against what you're designing. It does not explicitly name sibling alternatives or state exclusions (e.g., when to use audit_* or evaluate_design instead), which keeps it at a 4 rather than a 5.

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