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

Annotations only declare readOnlyHint, and the description adds real behavioral detail beyond that: ingest URL and token are deliberately withheld, disabled sources are 'paused', some sources are 'held by the plan', and routes_to_nobody has a precise definition. It even restates read-only, which is redundant but harmless. This is useful context an agent could not infer from the annotation alone.

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 sentences, front-loaded with the definition of the resource, which is the right order. However, the middle sentence is a dense run-on enumerating per-source fields that an existing output schema already covers, and the trailing 'Read-only.' duplicates the readOnlyHint annotation.

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?

The tool is a simple, zero-parameter read and an output schema exists, so the description is already more than sufficient for invocation. Its length is spent re-describing return fields the output schema likely details, rather than on anything an agent needs to call 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?

There are zero input parameters, so the baseline is 4 and there is nothing for the description to disambiguate. The field-level explanation of kind values (alertmanager, grafana, datadog, generic) and routes_to_nobody belongs to the return shape rather than inputs, but it still helps an agent interpret results.

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 concretely defines the resource — alert sources such as Prometheus Alertmanager, Grafana, Datadog, or a script, that feed alerts into incidents and rotations — so an agent knows exactly what is returned. It does not name or contrast with any sibling (e.g. list_notification_channels), which is the only thing separating it from a 5.

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?

Usage is only implied: reading this tells you how alert intake is configured for the org. The note that sources are set up in the Uptimepage app and that ingest URL/token are withheld does function as a mild 'don't attempt this via API' constraint, but there is no explicit when-to-use or when-not-to-use guidance and no alternative tool named.

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