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

Annotations already declare readOnlyHint=false and destructiveHint=true, so the safety profile is partly covered. The description adds the scope of what is mutated (the enumerated fields), but it does not warn what the destructive flag means here — e.g. whether omitted nullable fields are cleared — nor discuss permissions. It clears the lower annotated bar but adds only modest context.

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?

A single front-loaded sentence with no filler, listing the mutation surface efficiently. It is well-sized, though for an 8-parameter mutation the terseness edges toward under-specification rather than true conciseness.

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 an 8-parameter destructive mutation with nested objects, nullable fields and no output schema, one sentence leaves important gaps: partial-update semantics, brandId requirement, and how null values affect existing data. The description is not complete enough for an agent to call this safely without guesswork.

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 0% across 8 parameters, so the description must carry the burden. It conceptually groups several fields (visual identity covers logoUrl/primaryColors, audience covers targetAudience, schedule covers postingSchedule), which adds mild meaning, but it never addresses the required brandId or the standalone description field and gives no format or clearing semantics.

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 (Update) and resource (brand) and enumerates the mutable facets (name, voice, visual identity, audience, posting schedule), which clearly distinguishes it from create_brand, get_brand and list_brands in the sibling set. It stops short of naming those siblings explicitly, so an agent infers the routing rather than being told 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?

There is no when-to-use or when-not-to-use guidance, no mention of prerequisites such as needing an existing brandId, and no statement about whether this is a partial or full replacement update. The agent must infer usage entirely from the name.

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