trend

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It thoroughly explains the return structure (direction, min/max/latest, spill count, raw samples), edge cases (latest is null when the newest sample lacks a reading), and truncation behavior (samples limited to 200 rows, samples_truncated flag, and summaries over the full window). This is comprehensive and transparent.

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 description is well-structured: it opens with the core purpose, then details the output and truncation behavior. Every sentence adds useful information, and the formatting (backticks, line breaks) aids readability. It is slightly longer than necessary but not padded, earning a 4.

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?

The tool has no output schema, so the description must explain return values, which it does in detail. It covers the main purpose, all output fields, an edge case, and the truncation mechanism. For a tool of this complexity, nothing an agent needs to invoke it correctly is missing.

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?

The only parameter is 'hours' with a default of 1, and the schema provides no description (coverage 0%). The description mentions 'over the last hours' but does not elaborate on units, range, or whether fractional hours are allowed. It adds minimal value beyond the parameter name itself. Since the description does not fully compensate for the schema gap, a baseline of 3 is appropriate.

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 clearly states the tool reports a free-VRAM trend over a time window, with specific outputs (direction, min/max/latest, spill samples, raw samples). It explicitly differentiates itself from vram_status(), a point-in-time tool, so an agent can select it correctly. The verb 'trend' plus the resource (free VRAM) and time window make the purpose unambiguous.

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 explicitly states when to use this tool: to answer whether VRAM change was gradual or sudden, contrasting with vram_status() which cannot. It also gives guidance on sample truncation to manage context. However, it does not mention other alternatives like history() or ensure_free(), but the primary distinction is clear. It implies use when you need trend analysis rather than a snapshot.

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