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

Annotations already declare readOnlyHint=true, destructiveHint=false, openWorldHint=false, so safety is covered. The description adds genuine context beyond that: it falls back to the latest draft when no approved guide exists, and it characterizes the size/contents difference between compact and verbose responses.

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 tightly written sentences: the first front-loads what is returned, the second handles the compact/verbose decision. No filler or repetition.

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?

With no output schema, the description carries the burden of describing return content and does so thoroughly for both compact and verbose modes. For a read-only tool whose annotations cover the safety profile, nothing needed to invoke it correctly 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?

Schema coverage is 100%, so both parameters are fully documented in the schema, including the verbose tradeoff ('several times larger', internal fields/ids/provenance). The description largely restates that same tradeoff rather than adding new meaning, so the baseline 3 applies.

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?

States a specific verb (fetches) and resource (brand guide) and enumerates the exact content returned (identity, voice rules, palette, logo links, do/don't rules). This clearly separates it from siblings like update_brand_guide, generate_brand_guide, regenerate_brand_guide_section, and get_brand_brief.

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 verbose toggle gets explicit guidance ('Pass true only when you need the full stored record... rarely needed'), which is useful. However, nothing tells the agent when to reach for get_brand_guide instead of get_brand_brief, list_brands, or get_strategy; tool-level selection guidance is only implied.

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