list_failed

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

Annotations already declare readOnlyHint=true, so safety is covered. The description adds genuine behavioral context beyond that: the result ordering (newest first) and the inclusion of partially-failed deliveries alongside fully-failed ones, which shapes how the agent interprets results. It stops short of discussing pagination or result volume.

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 tight sentences with no filler; the scope and ordering are front-loaded, and the second sentence carries the workflow guidance without padding.

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 three-parameter, read-only list tool with no output schema, the description covers purpose, ordering, and the triage workflow. It could say slightly more about what fields each event row carries or result-volume expectations, but nothing essential to 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 description coverage is 100%, so the schema fully documents hours, limit, and source, including defaults and maxes. The description adds nothing about parameter syntax or behavior, so the baseline of 3 is correct.

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 (List), resource (webhook events), and filter scope (deliveries failed or partially failed) plus ordering (newest first). This clearly distinguishes it from siblings get_payload (inspect a payload), replay (redeliver), and send_test (synthetic send).

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?

Explicitly routes the agent: "Use this first when a webhook consumer is misbehaving," then names the follow-up tools get_payload and replay and the condition for each (inspect what was sent; redeliver once fixed). This is a complete when-to-use and what-next sequence.

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