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

With no annotations at all, the description carries the full burden and does well: it discloses the 20-report limit, the accepted report dialects, the FAA flight-category computation, and — most usefully — that undecodable tokens are returned with character offsets, which tells the agent how partial failures surface. It stops short of saying what happens on a wholly invalid report or whether errors are raised versus returned.

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 dense: purpose first, then the decoded field list, then the flight category, then the undecoded-token behavior. The long parenthetical earn its place as scope enumeration, though the missing terminal period and stacked clause structure make it read as one breathless sentence.

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, and the description sketches return shape only loosely ("structured fields" plus undecoded tokens with offsets). It omits any explanation of the `claims` verification results, which is a substantive part of the tool's behavior that an agent cannot infer from prose.

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 already documents both `reports` and `claims` with per-field descriptions and bounds. However, the description never mentions the `claims` verification capability at all, so a reader of the prose alone would not know that claimed temperature, dewpoint, wind speed or flight category can be checked against the decode. Baseline 3 applies, with a notable omission.

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?

The description opens with a specific verb+resource pair, "METAR / SPECI decoder with flight category," and then enumerates exactly what gets decoded (wind/gusts, visibility, CAVOK, RVR, clouds, altimeter, trend, RMK) plus the computed FAA category. An agent knows precisely what this tool produces and can tell it apart from anything generic.

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 only implied by the domain: it decodes aviation weather reports, accepts US and ICAO forms, and caps input at 20 reports. There is no explicit statement of when to use this versus an alternative service, no prerequisites, and no guidance on what to do with malformed input.

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