KPI trend by month

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds the meaningful trait of monthly granularity for a single metric, but says nothing about default period behavior, how far back the series goes, or what a 'series' contains.

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?

Front-loaded and short, which is good, but the entire second sentence is a verbatim copy of the schema enum — pure redundancy that occupies most of the description without adding information.

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?

No output schema exists, so the description carries some burden for explaining what comes back; 'month-by-month series' gives a hint but not the shape (list of periods? values?). With only three simple params and read-only annotations, it is minimally viable but leaves gaps.

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 67% and the description's metric list merely duplicates the enum already present in the schema, adding no new meaning. The 'one KPI' phrasing reinforces single-metric selection, but period and service semantics are left entirely to 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?

States a specific verb+resource: a month-by-month time series for a single KPI. The scope ('one KPI', monthly granularity) is clear, though it never names which sibling to prefer (get_mttr, get_dora_metrics) for the same underlying metrics.

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?

No when-to-use / when-not-to-use guidance and no mention of alternatives, despite siblings like get_mttr and get_dora_metrics covering overlapping metrics. The agent must infer that this tool is for trending a metric over time rather than a point-in-time snapshot.

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