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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds genuine context beyond that: the authentication rule (the agent's own secret or the workspace key, matching GET /v1/alerts) and the nature of the alerts surfaced. It omits rate limits and pagination behavior, keeping it from a 5.

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 the resource description front-loaded and the prerequisite second; nothing is padded. The credential sentence partially duplicates the schema, which is the only minor waste.

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 authentication is covered. Coverage is good but not exhaustive — no note on result ordering, pagination, or volume limits for a history-listing tool.

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 either/or credential semantics are already documented in the schema and the description largely restates them. Baseline 3 is appropriate — the description adds little parameter meaning beyond the schema.

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 a specific resource (alert history for an agent) and enumerates what it returns (80% budget warnings, spending spikes), which is concrete and distinct. It does not explicitly contrast itself with siblings like ledger_report or ledger_track, so it stops short of 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 implied — you call it to inspect an agent's alert history — and the credential prerequisite (agent_secret or workspace_key) is stated, which is real guidance. But there is no explicit when-to-use versus when-not guidance or named alternative among the siblings.

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