Invite a fan to a student's fan club

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

Annotations declare write/destructive/open-world, and the description adds substantial non-obvious behavior: an email is dispatched, a two-step confirmation fallback exists with a confirmToken that must never be invented or reused, and elicitation-capable clients take the prompt path instead. That is exactly the kind of side-effect and safety detail annotations cannot convey.

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?

Front-loads the action, then the side effect, then the confirmation protocol and safety constraint, in three dense sentences. Slightly heavy on parenthetical asides but no wasted sentences.

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 no output schema, it covers the critical unknowns: that mail is sent, the preview-first fallback, and the token contract. It could say a bit more about what the phase-1 preview response contains or what success returns, but an agent has enough to call it correctly.

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 confirmToken is already documented in the schema. The description restates the name+email intent and the confirmToken rule but adds no syntax or sourcing detail beyond the schema (e.g., relationship_id sourcing stays in the schema). Baseline 3 applies.

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 (invite) and resource (someone to follow a student's Artsonia portfolio), plus the effect (sends an invite email). It is clearly distinguishable from read-oriented siblings like artsonia_get_fans or artsonia_list_students.

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 operating conditions: confirm first, use only authorized real addresses, test with @example.com. It does not name a sibling alternative (e.g., checking existing fans via artsonia_get_fans before inviting), so it stops short of full when/when-not routing.

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