list_styles

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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the read-only behavioral trait is covered structurally. The description reinforces this with 'Read-only.' and adds the discovery workflow context. With strong annotations, the description adds value by framing the tool's role as an entry point rather than repeating safety traits.

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?

Three short sentences, zero waste. Front-loaded with the core purpose, then the behavioral note, then the usage directive. Every sentence earns its place.

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 zero-parameter discovery tool with both readOnlyHint and idempotentHint annotations plus an output schema, the description fully covers what's needed: what it returns (styles with targets), how it fits the workflow (call first, feed results elsewhere), and its safety profile (read-only). Nothing essential is missing.

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?

The tool has zero parameters and schema coverage is 100% trivially (empty properties object). No parameter documentation is needed since there are none. The description correctly focuses on the output relationship (style names feeding into other tools) and what 'targets' are included in results, which provides the value the schema can't.

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?

Clear purpose: 'List all available mixing styles with their targets.' Specific verb (list) + resource (mixing styles) + scope (all, with targets). Distinguishes from siblings since get_style retrieves a single style while this lists all, and suggest_style recommends one. Slight deduction because it doesn't explicitly contrast with suggest_style's purpose, but the verb+resource+scope is strong.

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?

Excellent guidance: 'Call this first to discover style names; pass one to get_style, auto_mix or preview_mix.' This explicitly says when to use it (first, for discovery) and tells the agent which sibling tools consume its output. This is a model of usage direction.

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