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

Annotations only cover the safety profile (readOnlyHint=false, destructiveHint=false); the description goes well beyond by disclosing the 3-free-team quota, the exact error shape, and the instruction to relay rather than retry. It also documents the return payload (join_url, join_link_expires_at, join_link_uses_remaining) in the absence of an output schema.

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 and ownership come first, then parameter guidance, then the failure mode and return value. Every sentence carries non-redundant information with no filler despite the density.

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 compensates by describing return fields, and it also covers the quota-exhaustion error path and the sibling routing. Nothing an agent needs to call this correctly is missing.

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%, so the baseline is 3; the description nonetheless reinforces the enum meaning of 'ref' with surface-level context ('SOLELY when creating in response to the offer') that the schema text states more tersely. The name parameter is only restated, so credit is marginal rather than substantial.

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+resource ('Create a new team') and adds the ownership consequence ('they become the owner'), which is behaviorally meaningful. It also implicitly distinguishes itself from the sibling teams-invite by assigning self-join to this tool.

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?

Gives explicit when-to-use for the ambiguous 'ref' parameter (only when responding to the me → suggestions.create_team offer) and an explicit exclusion (omit when unprompted). It names the alternative teams-invite and the exact condition that selects it (user names a specific address).

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