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

Annotations establish the safety profile (not read-only, idempotent, non-destructive), and the description adds real context beyond them: candidates stop seeing the profile while paused, and already-taken requests are retained regardless. It does not mention response shape, but an output schema exists so that burden is reduced.

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 tight sentences with no filler, leading with the authentication prerequisite and then the two effects. Slightly better if the auth sentence were not first, but overall well front-loaded.

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 3-required-parameter mutation with an output schema and good annotations, the description covers prerequisites, both operations, visibility side effects, and retention of existing claims. An agent has everything needed to invoke 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 coverage is 100%, so the baseline is 3; the description adds meaning beyond it by clarifying that the cap counts requests 'taken, not finished' — i.e., lowering the cap does not drop in-flight claims ('requests already taken are kept either way'). That behavioral nuance is not expressed in the schema.

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 specific verbs (pause/resume, set a cap) on a specific resource (one of the user's referrer registrations), and the title-level framing 'cap how many I hold' is restated concretely. It is clearly separable from siblings such as update_referrer_profile, set_referrer_email_notifications, and register_as_referrer.

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 clear context: requires sign-in, and operates on one registration identified via list_referrer_registrations. It does not explicitly name an alternative tool or state when-not to use it (e.g., versus update_referrer_profile), so it stops short of full routing guidance.

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