ensure_free

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

With no annotations, the description carries the behavioral burden and does meaningful work: it discloses that claimed/busy models are skipped unless force=True, that by writes to the audit log, and that reserved_mb can be None if unreadable. It does not describe failure behavior when enough VRAM cannot be freed, but the core side effects are 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?

Three tight sentences; the main action is front-loaded, followed by parameter semantics and the return signal. No filler or redundant phrasing.

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?

It explains the return signal (reserved_mb, with a None fallback), which matters because there is no output schema. It could add failure semantics, such as what happens if the target cannot be reached, but the essential invocation details are present.

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 0%, yet the description defines all three parameters: gb as the target free amount, force as the override for claimed/busy models, and by as the audit-log requester. This fully compensates for the bare 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 and resource: 'Free VRAM until at least gb GB is available.' It also adds distinguishing behavior ('Skips claimed/busy models unless force=True'), making it easy to tell apart from siblings like unload, release, and reserve.

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?

Provides clear context: call when you need a guaranteed amount of free VRAM, with force controlling whether claimed/busy models may be displaced. It does not explicitly name sibling alternatives or state when not to use it, so it stops short of full routing guidance.

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