Update tracking email settings

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

Annotations already declare the mutation profile (readOnlyHint=false, destructiveHint=false, openWorldHint=true), so the description's job is to add what those don't say. It does: partial-update semantics and the fact that the response mirrors get_tracking_email_settings. It doesn't address the non-idempotent hint or confirm what happens if no parameters are passed.

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?

Two sentences, no filler. The behavior statement is front-loaded and the return-value clarification follows immediately, so an agent gets the essentials in the first line.

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?

There is no output schema, and the description compensates by saying the result matches get_tracking_email_settings. Combined with the partial-update rule and the annotated safety profile, an agent has enough to invoke it correctly. A note on the no-argument case is the only real omission.

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%, and the enum plus the '+24 hours is next day 9:00 AM' clarification already live in the schema. The description only restates the two concepts (on/off and delay after purchase) without adding format, defaults, or interaction detail. Baseline 3 is appropriate when the schema carries the parameter burden.

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 ('turns default tracking emails on or off and sets their delay after purchase'), which is more precise than the tool name alone. It also names the read counterpart get_tracking_email_settings, so an agent can distinguish the write tool from its sibling without opening either schema.

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 sentence 'Changes only what you pass' tells the agent this is a partial update and that omitted fields are left alone, which is the key usage decision for this tool. It also points at get_tracking_email_settings as the read path. It stops short of explicit when-not-to-use guidance, which keeps it below a 5.

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