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

Annotations already declare readOnly/idempotent/non-destructive, so the safety bar is met; the description adds real domain behavior beyond that — Forge cohorts surface only as their first session, weekly sessions are never listed, and registration status appears only for signed-in users. These are non-obvious output traits an agent would otherwise guess wrong.

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?

Purpose is front-loaded, and with no output schema some return-field explanation earns its place. However, the single sprawling paragraph mixes list semantics with per-field prose and meta-instructions ('the Captain's copy leaves them out'), which makes it harder to scan than it needs to be.

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 usefully documents the returned fields (`about`, `cadence`, `when`, `startsAt`/`endsAt`, link, registration flag) and ordering, which is the bulk of what an agent needs. It omits input-side details (type, limit) and any pagination/truncation behavior, keeping it short of complete.

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 only 50% (limit is undocumented), and the description compensates not at all for inputs — it discusses output fields (`about`, `cadence`, `when`, `startsAt`/`endsAt`) and never explains the `type` filter or `limit`. The parameters are simple enough that the gap is survivable, but the description adds no input-side meaning.

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 opening clause names a specific verb+resource+scope (upcoming Pirate Skills events, soonest first by date) and adds return-shape detail (a link per event, registration status for signed-in users). It also explicitly distinguishes itself from the sibling my_forge_sessions for cohort/session questions, so an agent can route without opening either schema.

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?

It gives an explicit alternative and the condition that selects it ('When the person asks about their own Forge cohort or its sessions, use my_forge_sessions instead'), plus a scoping rule that Forge cohorts appear only as their start. It lacks broader when/when-not guidance (e.g. vs get_offers or register_for_event), so it falls short of a full 5.

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