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

Annotations already establish readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds genuine behavioral context beyond that: the output carries deployment markers marking PR merge points, which tells the agent the timeline interleaves score data with deploy events. It omits pagination/return-shape details, but for a safe read tool this is solid.

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?

One front-loaded sentence covering what it returns, followed by three brief exemplar queries. Nothing is padded, though the three example questions are somewhat redundant with each other and could be trimmed to two.

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?

With no output schema, the description must characterize the return value, and it does: daily granularity plus deployment markers. Combined with a fully-documented 3-parameter schema and read-only annotations, an agent has enough to call it correctly; only the exact response shape stays unspecified.

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%, with defaults and maxima (days default 30, max 365) and a superadmin-only note on customerId already documented. The description only restates the date-range and agent scoping, adding no format or edge-case semantics. Baseline 3 applies when the schema does the heavy lifting.

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+resource ('Daily score timeline for an agent over a date range') plus a distinguishing detail: deployment markers tied to PR merges. This separates it from get_fleet_timeline (fleet scope) and get_deployment_impact by implication, but it never names or contrasts with those siblings 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?

Three quoted example questions ('did overall performance improve after our fixes?', 'show me the score trend', 'what happened to scores this week?') give concrete scenarios for selecting this tool. There is no explicit when-not guidance or named alternative (e.g., use get_fleet_timeline for cross-agent views), which keeps it below a 5.

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