Get a profile

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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the 'Read-only.' sentence adds nothing. The genuinely additive content is the explicit exclusion list — no passwords, 2FA, cookies or proxy credentials — which tells the agent up front that credential fields cannot be retrieved this way and prevents futile follow-up calls.

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?

One dense sentence lists the payload, a second excludes sensitive fields, a third restates the annotation. Front-loaded with the resource and detail level, no filler. The trailing 'Read-only.' is redundant against readOnlyHint=true and is the only wasted sentence.

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 does the work of describing the return payload field-by-field and, importantly, its boundaries (credentials excluded). For a simple one-parameter read tool this covers everything an agent needs before calling, with the safety profile already handled by annotations.

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?

There is a single required parameter described in the schema at 100% coverage ('Profile id.'), so the description has nothing meaningful to add. 0-parameter tools get a baseline 4, but with one fully documented parameter the baseline 3 applies; the description neither adds format hints nor says what happens on an unknown id.

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 ('One profile in detail') and enumerates exactly which fields come back (group, tags, notes, start URLs, proxy/fingerprint summaries, timezone, language, location, WebRTC). It implicitly separates itself from list_profiles by being single-record and detailed, but never names the alternative, so it stops just short of the top band.

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 only implied: 'one profile in detail' suggests use when full record data is needed rather than a listing. There is no explicit when-to-use, when-not-to-use, or reference to list_profiles/update_profile as alternatives, leaving the agent to infer the routing itself.

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