hey_collection

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

Annotations already indicate idempotence and non-destructiveness, and the description adds the return format ('Returns {success, error?}'), which is valuable beyond the annotations. No contradiction between description and annotations.

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?

The description is two sentences, front-loaded with the core action, and every word adds value. No redundancy or unnecessary details.

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?

Given the moderate complexity (3 parameters, no output schema) and the presence of good annotations, the description is adequate. It covers the return type and provides a discovery hint, though it could optionally clarify the effect of the action (e.g., that it toggles membership). Overall, complete enough for effective use.

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 input schema already describes each parameter. The description adds minimal extra meaning beyond repeating the schema, except for referencing 'hey_list_collections' in the collection_id description. 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?

The description clearly states the verb ('add or remove') and resource ('email thread from a collection'), making the tool's purpose obvious. It distinguishes itself from sibling tools by referencing 'hey_list_collections' for discovery, but does not explicitly differentiate from other collection-related tools.

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 description provides a useful hint to use 'hey_list_collections' to find collection IDs, but does not give explicit guidance on when to use this tool vs alternatives (e.g., 'hey_list_collection_emails' to view current members) or when not to use it. The usage context is implied rather than stated.

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