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

With no annotations, the description carries the full burden. It discloses the returned fields, which usefully implies a non-mutating read, but says nothing about failure behavior for an expired/revoked token, side effects, or permissions. The schema's token description partially compensates by explaining token lifetime, keeping this at a minimum-viable 3.

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 that lists only the returned fields, with no filler or restatement of the title. Every clause earns its place.

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 correctly enumerates the return payload, which is the essential information for this tool. It is nearly complete; only error/expiry handling for the token is left implicit (and is partly covered by the schema's token description).

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% and the token parameter is thoroughly described in the schema (origin, bounded lifetime, revocation handling). The description adds no additional meaning about the token, so the baseline 3 for schema-covered parameters 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?

The description states a specific verb ('Return') and resource ('the current session') and enumerates the exact fields returned (name, admitted time, expiry, budget spent). This clearly separates it from write-oriented siblings like lockzone.post and lockzone.leave, though it never names those alternatives explicitly.

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: an agent can infer this is the introspection call for checking session state, but there is no explicit 'when to use' or 'when not to use' guidance relative to siblings such as lockzone.protocol or lockzone.read. No prerequisites or exclusions are stated.

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