brand_build_matrix

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

No annotations are provided, so the description carries the full burden. It discloses the dependency on strategy.yaml, describes the output (variant grid with status tracking), and implies different behaviors per mode. It could mention whether operations are destructive, but the modes suggest generate creates, edit modifies, view is read-only.

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 four sentences, front-loaded with the main purpose. Each sentence adds unique value: purpose, modes, prerequisite, return format. No wasted 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?

For a tool with 3 parameters, no output schema, and no annotations, the description provides all necessary context: what it does, how to use it (three modes), prerequisites, and what the output looks like. It is sufficient for an agent to decide when and how to invoke it.

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%, but the description adds context beyond the schema by explaining how each mode uses parameters: 'Mode 'generate' creates variants using persona tensions...' and 'Mode 'edit' refines a specific variant by ID'. This enriches the enum and conditional usage.

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 starts with a clear verb+resource: 'Generate persona x journey stage messaging variants'. It distinguishes the tool from siblings by specifying it works across all personas and stages, while siblings like brand_build_personas and brand_build_journey likely focus on individual components.

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 explicitly states three modes and their contexts (generate, view, edit), and includes a prerequisite: 'Requires personas and journey stages in strategy.yaml'. This tells the agent when to use the tool and when not to. It does not explicitly name alternatives, but the sibling list provides context.

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