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

Annotations already mark this as read-only, and the description aligns by stating it 'Returns' source code rather than mutating state. It also goes beyond annotations by detailing the exposed API (window.__coachWait, window.__coachWatch.status, window.__coach) and noting it also returns the rig version and bot surface URL, giving a full picture of what the returned payload does when executed.

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 sentences pack essential information without fluff: the main return value, the runtime behavior, the exposed API details, and auxiliary return values. The most important claim is front-loaded ('Returns the JavaScript source'), and each subsequent detail earns its place by clarifying what the returned code provides.

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 read-only tool with no parameters and no output schema, the description fully equips an agent to invoke it correctly. It states the target context (chess.com bot game), how to use the returned source (run in page via javascript tool), what the source exposes, and what other data is returned (version and URL). Nothing necessary 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?

There are no parameters, so the baseline is 4. The description does not need to explain parameter semantics because none exist; the zero-parameter schema is fully covered by the absence of parameters.

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 identifies a specific verb ('Returns') and resource ('the JavaScript source of the in-page coaching rig for a chess.com bot game'), making the tool's purpose unmistakable. It also distinguishes itself from the sibling analysis tools by focusing on an in-browser rig rather than analysis or review.

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 gives clear context: the returned source is to be run in the chess.com bot game page via the browser's javascript tool. It implies the use case but does not explicitly contrast with alternative tools or state when not to use it. Still, the context is strong enough for an agent to select this tool when a live-coaching rig is needed.

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