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

Adds substantive context beyond the annotations: the auth requirement ('Needs the user's personal access token') and, critically, the temporal semantics of a filter change ('A new filter starts from now: jobs already open are not emailed'). That non-obvious side effect is exactly the kind of behavior an agent cannot get from readOnlyHint/destructiveHint/idempotentHint.

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 short sentences, front-loaded with the operation set, followed by the caveat and the prerequisite. No filler and no repetition of schema content.

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-parameter mutation tool with full schema coverage, annotations, and an output schema, the description supplies everything else an agent needs: the operation set, the side effect of replacing a filter, and the token requirement. Nothing material 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 each nested filter field carries its own description, so the schema already does the heavy lifting. The description reinforces replace-not-merge semantics for `filter`, but the schema's own 'It replaces the old one' already states that, so the added value is marginal.

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 the specific resource (a job alert) and enumerates the exact operations available: pause, resume, or replace the filter. This is immediately distinguishable from the sibling write tools create_alert and delete_alert, which cover creation and removal rather than modification.

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 three supported mutations define the scope of use clearly, so an agent knows this is the tool for toggling or retargeting an existing alert. It stops short of explicit routing language (e.g. 'to remove an alert use delete_alert', 'to see alerts use list_alerts'), so the exclusion side is left to inference from sibling names.

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