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

With no annotations present, the description carries the full behavioral burden. It does well on mechanics: it discloses that scoring is a 'fixed-weight heuristic,' describes the smoothing into a trailing curve, and defines a stall as a span falling well below an earlier peak, which signals deterministic, explainable output rather than an opaque model call. However, the final sentence is truncated ('A fixed-weight heurist'), so any further disclosure — likely about determinism, reproducibility, or limits — is lost, and nothing is said about failure/rejection behavior for too-short input.

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?

The output is front-loaded — the headline action (plot curve, flag stalls) comes first, followed by the scoring formula and then the audience. It is dense but every clause is substantive. The one real flaw is the dangling, cut-off final sentence, which reads as an unfinished thought and wastes the closing position.

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?

For a 7-parameter analytical tool with no output schema, the description needs to sketch the return shape; it partially does by promising a per-sentence curve plus reported stall spans, but it never indicates whether results include numeric per-sentence scores, the peak location, or how stalls are delimited. Combined with the truncated ending and no statement of what happens when `minSentences` is not met, an agent can call it but cannot fully predict the payload.

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 100%, so every parameter is already documented in structured form, and the description adds only marginal meaning: it explains that supplying `actionWords` renormalizes the other weights (corroborating the schema) and that the curve is a smoothed trailing average. It never explains `expect`, `peakThreshold`, `stallDrop`, or `minSentences` in prose, but those are fully covered by the schema, so the baseline 3 applies.

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 names a specific verb and artifact — 'plot a prose intensity curve per sentence and flag where a tense passage loses velocity' — and then enumerates the exact signals it scores (sentence length, one-syllable share, exclamation/question marks, optional action words). That is well beyond a restatement of the name. It stops short of a 5 because it never contrasts itself with any neighboring tool (e.g. a general prose-forensics auditor), so the agent must infer which analysis tool to pick.

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?

It states a clear use case: 'For a writing tool or editor agent checking an action or tension scene.' That gives the agent a concrete trigger condition. It offers no explicit exclusions or alternatives, and it does not mention the contrasting behavior of the `expect` mode ('tense' vs 'any') in prose — that distinction is left entirely to the schema.

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