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

Annotations already declare this is a non-read-only, non-destructive, non-idempotent, open-world mutation, so the safety profile is covered. The description adds one valuable trait – the outcome is a pending application that a leader later decides on, i.e., not an immediate membership grant – but omits auth requirements, failure modes, or rate limits.

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 action before the endpoint and payload detail. Every element is relevant, though the parenthetical request-body listing is slightly noisy since the schema already defines those fields.

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 3-parameter mutation with no output schema and annotations that cover only the safety profile, the description states the effect and outcome the agent gets back. It still leaves gaps on the auth prerequisite (social cookie) and what happens on duplicate/rejected applications, so it is adequate but not 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 67%: 'social' and 'requestId' are already documented in the schema (including the idempotency-key semantics), while squadId carries no schema description. The description only restates the body fields {squadId, requestId} without adding format, sourcing, or constraint detail, so it does not compensate for the uncovered parameter.

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?

States a specific verb and resource ('apply to join a Squad') and even pins the endpoint and body shape, which is more than the name alone conveys. It does not explicitly distinguish itself from siblings like memeswap_squad_create or memeswap_squad_directory, but 'apply to join' is unambiguous enough that the agent can separate it from those.

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 leading 'Use to apply to join a Squad' gives implied context for invocation, but there is no statement of when not to use it, no alternative tool named for related goals (e.g., squad_directory for browsing before applying), and no prerequisite such as needing a social session first.

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