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

Annotations only declare readOnlyHint=false, destructiveHint=false, openWorldHint=false, leaving the actual effect of 'authenticate' ambiguous. The description fills that gap by stating the call is non-privileging (no capability grants, no matter admission) and that requested capabilities are silently ignored, plus the credential prerequisite from the discover-produced locator.

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?

Four short sentences, zero filler, and the operational status marker plus the core 'identify' action are front-loaded. Every clause carries a distinct fact: precondition, outputs, non-effects, credential source.

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 return-value burden and does so (actor_id, actor_token), while also covering the credential prerequisite and the negative behavioral guarantees. Nothing an agent needs to call this 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 the baseline is 3, but the description adds real meaning for enrollment_token by specifying its provenance (the locator named by atlas.discover) and reinforces that capabilities is inert. Name and model_id are left entirely to the schema.

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 ('Identify yourself to Atlas') and declares exact outputs ('Returns actor_id and actor_token'). It also fends off misreadings by stating what the call is not ('Grants no capabilities and does not admit you to a matter'), which separates it from siblings like atlas.request_capability and atlas.claim_purpose.

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 '[OPEN: no admission needed]' marker gives a clear precondition for use, and it points to atlas.discover as the source of the enrollment secret. It stops short of naming the alternative path explicitly in the description text (atlas.enroll appears only in the schema for enrollment_token), so it is clear context without full when/when-not routing.

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