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

Annotations already cover readOnly, idempotent, and non-destructive. The description adds value beyond them by disclosing an edge-case return ('Returns null when no brand exists') and clarifying that it does not start an agent session, which meaningfully distinguishes it from session-oriented siblings.

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 tight sentences with no waste: the read scope is front-loaded, the null edge case follows, and the side-effect disclaimer closes. 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 single-parameter read tool with no output schema and full annotation coverage, the description supplies the scope of returned data, the null case, and the no-side-effect guarantee. 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 description coverage is 100% and the single projectId parameter is fully documented in the schema, so the description is not required to carry parameter meaning. It adds nothing beyond the schema, matching the baseline of 3.

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 ('Read') and resource (the project's saved brand kit), and enumerates the contents returned (business info, overviews, colors, fonts, logo marks, personas). It does not name the closely related mutating sibling create_or_update_brand_kit, though 'Makes no changes' implicitly contrasts with it.

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?

Usage is implied by the read framing and the 'Returns null when no brand exists' edge case, which helps the agent interpret an empty result. However, there is no explicit when-to-use vs. when-to-use-alternative guidance against create_or_update_brand_kit or other brand-related siblings.

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