Resend an invitation

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

Annotations already declare readOnlyHint=false, openWorldHint=true, and idempotentHint=false. The description adds meaningful context beyond those: this actually sends a real email (an external side effect), requires user confirmation, and only applies to a subset of invitations. It does not, however, say anything about rate limits, duplicate-resend behavior, or failure modes.

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?

Three short sentences, each doing distinct work: the core action plus confirmation warning is front-loaded, followed by the eligibility constraint and the id-lookup pointer. No filler.

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 annotations covering the safety profile and an output schema covering return values, the description fills exactly the remaining gaps: side-effect disclosure, confirmation requirement, eligibility precondition, and parameter provenance. Nothing an agent needs to invoke it 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 schema already documents the kind enum and invite_id. The description adds provenance for invite_id ('Use invite_list to find the id'), which is mildly useful, but does nothing for the kind parameter. Baseline 3 applies when the schema carries the load.

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 ('Sends another real invitation email to the original recipient') with clear scope. It explicitly distinguishes the eligible case (a Tailscale-emailed invitation) from the ineligible one (print_link), so an agent can tell it apart from siblings like invite_user or invite_revoke.

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 a clear precondition ('only works for an invitation Tailscale emailed; a print_link invitation has no recipient to email') and a pointer to invite_list for obtaining the id. It even calls out the need to confirm with the user first. It stops short of naming the alternative tool to use for the print_link case, so it is not a full when/when-not/alternatives statement.

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