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

Annotations already declare readOnly, idempotent, non-destructive, closed-world behavior, so the bar is lower. The description adds genuine context beyond them: the returned fields (Build weeks 1-6, Grow weeks 7-12, sessions left, in-status) and the no-access edge case returning empty with hasAccess false.

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 sentence that front-loads the resource and scope before the return fields and edge case. It is dense but every clause carries information; only the length of the phase-week parenthetical makes it feel slightly run-on.

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 parameters and no output schema, the description correctly compensates by describing the return content and the empty/no-access outcome. Nothing critical for correct invocation is missing, though the absence of guidance on how it relates to join_forge_cohort leaves a small gap.

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?

The tool takes zero parameters, so there is nothing for the description to disambiguate and the baseline of 4 applies. No parameter claims are made that could conflict with the empty 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?

The description names the specific resource (Pirate Forge live sessions for the signed-in person) and scopes it to joinable sessions, distinguishing it from list_events and join_forge_cohort. It reads as a return-content noun phrase rather than a verb+resource statement, but an agent can still identify the tool's function unambiguously.

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?

There is no explicit when-to-use guidance and no mention of alternatives such as join_forge_cohort or my_access. The usage is only weakly implied by 'the signed-in person can still join', leaving the agent to infer when this should be called instead of the sibling tools.

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