List alias contacts

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

Annotations already establish the read-only, idempotent, non-destructive profile, so the bar is lower; the description goes further by disclosing pagination granularity (20 per page), the zero-based page origin, and the exact fields each returned contact carries. It does not mention ordering or rate limits, but it meaningfully adds behavioral context beyond the 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?

Front-loaded with the core purpose, then the contact anatomy and finally the pagination convention; every sentence contributes. It is slightly dense in the middle clause enumerating fields, but there is 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?

For a simple two-parameter read-only list with no output schema, the description is essentially complete: it explains scope, page size, page origin, and the shape of the returned records. Ordering and empty-result behavior are the only unstated details.

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%, and the schema itself already states that page_id is zero-based, defaults to 0, and yields 20 contacts per page, so the description's pagination note largely duplicates it. The only marginal addition is framing alias_id as a single-alias scope rather than a general filter.

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?

Names a specific verb and resource ('List the contacts ... for a single SimpleLogin alias') and immediately clarifies what a contact is (a reverse alias). This clearly separates it from siblings like contact_create, contact_set_blocked, and contact_delete, which act on the same object.

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 implies when to use it by scoping the operation to a single alias, but never states when to prefer it over alternatives (e.g. contact_create for adding, contact_set_blocked for toggling forwarding) or any prerequisite for holding a valid alias_id. Usage is inferable rather than explicit.

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