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

With no annotations, the description carries the full behavioral burden. The parenthetical '(wallet token)' hints that token is a wallet credential, but the description says nothing about auth requirements, idempotency, error behavior for an invalid/expired code, or what joining entails.

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 with no wasted words. It is efficient, though the parenthetical placement makes the token/code mapping slightly ambiguous on first read.

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 mutation tool with two required params, no annotations and no output schema, a one-line description is thin. Auth expectations, failure modes, and post-join effects are all left for the agent to guess.

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 0%, so the description must compensate — and it does for both params, mapping 'code' to an invite code and 'token' to a wallet token. This is meaningful disambiguation beyond the bare string types, though it stops short of format details.

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?

Clear verb+resource: 'Join a crew by invite code' tells the agent exactly what the tool does and the mechanism used. It implicitly differentiates from the sibling join_official_crew by specifying the invite-code path, but never names it 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?

The phrase 'by invite code' implies the precondition for using this tool (you must possess a code), which separates it in spirit from join_official_crew or join. However, no alternative is named and no when-not guidance is given, so usage is only implied.

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