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

Goes well beyond the annotations: discloses a hard cap ("Up to 5 alerts per account"), a non-obvious email-routing quirk ("the address the account had when the token was made"), and an auth requirement. The annotations only say this is a non-idempotent, non-destructive write; the description supplies the constraints and consequences that actually shape a correct call.

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?

Four short sentences, each carrying distinct information — behavior, cap, email routing, permission gating. The core purpose is front-loaded and nothing is redundant.

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?

An output schema exists so return values need no explanation, and the description still covers the things the schema cannot: account limit, token scope, email destination, and the consent gate. Nothing essential for a correct invocation is missing.

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 every filter field is documented in the schema with examples, so the schema carries the parameter burden. The description only refers to "the filter" generically and adds no matching semantics (e.g. how multiple fields combine) beyond what the schema states.

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 opens with a specific verb and resource ("Create a job alert") and immediately explains what the artifact does: emails matching new jobs on the user's preference schedule. It is clearly distinct from list_alerts/update_alert/delete_alert by verb alone, though no sibling is named explicitly.

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?

"Create one only when the user asks for it" is an explicit when-to-use constraint backed by a prerequisite ("Needs the user's personal access token"). It does not name alternatives for editing an existing alert, but the gating guidance is concrete rather than implied.

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