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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world). The description adds genuinely new behavioral context: nothing about a matter, objective, evidence, filing, authority, or room is disclosed before admission, and authentication/enrollment do not themselves admit you. That gating behavior is not derivable from the annotations or schema.

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?

The open-access constraint is correctly front-loaded in brackets, and the description is short. However, the closing two sentences are redundant ('Authentication and enrollment grant nothing. Enrollment does not verify a principal and does not admit you') and the text is more atmospheric than informative.

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 zero-required-parameter entry-point tool with no output schema, an agent needs to know what discovery yields — capabilities, context, or a pre-admission view? The description explains the gate but not the payload, leaving the core value of the call undefined.

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 both parameters are already documented. The description only adds the consequence of omitting actor_token ('you are outside'), which the schema already frames as an optional credential. Baseline 3 is appropriate when the schema carries the parameter 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?

The description establishes that atlas.discover is the 'front door' usable without admission, which does differentiate it from admission-gated siblings like atlas.enter_room. However, it never states what the tool actually returns or does once called — no verb+resource for the output. An agent knows it is allowed to call it, but not what it gets back.

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?

'[OPEN: no admission needed]' and 'With no actor_token you are outside' imply this is the tool to call before enrolling or authenticating. That is useful implicit routing, but there is no explicit 'call this first, then use X' statement and no comparison against siblings like atlas.enroll or atlas.authenticate.

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