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

Annotations already declare non-read-only, non-destructive, closed-world behavior, so the description's job is to add context — and it does: the governing-role authorization requirement and the fact that allowGuests lets people join without an account. It omits any note on link expiry, revocation, rate limits, or idempotency, so it stops short of a 5.

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 route are front-loaded in the first clause, followed by the authorization prerequisite and optional-parameter notes — a logical order. It is a bit dense, stacking an implementation note ('matches POST /api/projects/[id]/shares/token since 2026-08-19') and parentheticals into one long sentence.

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 four-parameter mutation tool with no output schema, the description covers the key facts an agent needs: what is created, the link format, the required role, and the guest-join behavior. It does not describe the returned token/link shape explicitly, which is a minor gap.

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 100%, so every parameter (including expectedProjectId and its refusal semantics) is already documented in the schema. The description's mentions of the 'viewer' default and allowGuests default true largely restate the schema, so baseline 3 is appropriate.

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 ('Creates a shareable invite link for a project') and even names the resulting artifact (/join/<token>), so the output is concrete. It also clarifies the mechanism is identical to the app's own 'Share' button, which removes any ambiguity about what is being produced.

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 prerequisite: a GOVERNING role (owner or manager) is required, which tells the agent when this call will succeed. It does not, however, point to any alternative or sibling tool for related sharing/permission operations, nor state when not to use it.

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