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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and non-destructive behavior. The description adds meaningful context beyond those: the upstream data source (environment.data.gov.uk/flood-monitoring), the UK Open Government Licence, and that no auth is required. It also discloses the exact fields returned, which helps set expectations without contradicting any annotation.

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 dense sentences with no filler: the first states action and filters, the second lists return fields, the third covers data source/license/auth. Key scoping information ('currently active', 'England') is front-loaded, and every sentence earns its place.

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?

Given the rich input schema, abundant annotations, and existence of an output schema, the description is nearly complete. It covers filters, return contents, data provenance, licensing, and auth. The only minor gap is no explicit note on how filters combine (e.g., whether county and radius can be used together), but the schema's per-parameter 'use with' notes partially cover this.

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 every parameter (lat, long, dist, county, min_severity) already explained in the input schema. The description mostly restates the severity scale and filter options already present in the schema, adding no genuinely new parameter-level meaning. Baseline 3 is appropriate when the schema carries the semantic load.

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?

Description opens with a specific verb ('Get') and resource ('currently active flood warnings and alerts for England from the UK Environment Agency'), immediately distinguishing it from sibling station-focused tools like uk-ea-flood-monitoring.stations.readings and uk-ea-flood-monitoring.stations.search. It also enumerates filter options and return fields, leaving no ambiguity about what the tool does.

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?

The description clearly frames the tool as returning current warnings/alerts and names all filter dimensions, giving an agent clear context for when to call it. However, it does not explicitly say 'use stations.search for station data' or mention any exclusion cases, so it stops short of explicit when-not guidance.

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