engine_status

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

The annotations already declare readOnlyHint, destructiveHint false, and openWorldHint false, so the safety profile is covered; the description reinforces the closed-world claim concretely with 'No uploads or downloads', which tells an agent this is a cheap local probe. However, it says nothing about what the check reports (dependency presence, model cache state) or whether it can be slow, leaving the actual behavior of the call underspecified.

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?

Two short sentences, front-loaded with what is checked and followed by the key scoping constraint. No filler, no restatement of the tool name.

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 status/probe tool the returned information is the entire value proposition, and there is no output schema, so the description should at least sketch what the check reports (e.g., availability of engine components and whether the transcription model is cached). It covers inputs and safety adequately but leaves the outcome shape to guesswork.

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 tool takes zero parameters, so there is nothing for the description to disambiguate and the schema is trivially complete.

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 gives a specific verb ('Check') and a specific resource pair ('local video engine dependencies' and 'cached transcription model'), which an agent can clearly distinguish from action tools like transcribe or media_add. It stops short of naming which sibling to prefer when it comes to verifying transcription readiness, but the purpose itself is unmistakable.

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: an agent can infer this is a pre-flight check to run before transcribe or export operations, but the description never says 'call this before X' or when a result should block a follow-up call. The 'No uploads or downloads' clause constrains scope rather than prescribing when to invoke it.

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