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

Goes well beyond the annotations, which only declare the non-read-only/idempotent/non-destructive profile: it adds credit cost, the low-confidence confirmation branch instead of silent save, and explicit auth mechanics (OAuth prompt or Bearer acd_live_ key). It does not clarify whether saving overwrites or duplicates an existing profile, which matters for a write tool flagged idempotent.

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 sentences, front-loaded with what is read and saved, then cost/confidence behavior, then the auth requirement last. No filler, and each sentence carries distinct operational information.

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 an output schema present, return values need not be described, and the description covers cost, auth, and the confirmation escape hatch. The one gap is the write semantics of persist (create vs overwrite on an existing brand profile), which is material for a tool with destructiveHint=false and idempotentHint=true.

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%, so url, mode, and persist are already documented in the schema, including the enum and both defaults. The description adds no parameter-level detail (e.g., what persist=false does to the confirmation flow), 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 and resource ('Read a brand's website and save a brand profile') and enumerates exactly what the profile contains (name, value props, CTA, tone, product images). An agent can distinguish it from the read-only sibling list_brand_profiles without opening either schema.

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?

Provides useful operating context (no credit cost, low-confidence reads returned rather than saved, sign-in required), but never states when to prefer this over alternatives such as list_brand_profiles or refresh_canvas, nor what happens when a profile already exists for the brand.

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