take_screenshot

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

Annotations declare readOnlyHint=true, which is consistent. Description adds valuable behavioral details: returns base64 inline, saves to .mcp/screenshots/, and error conditions (no session, timeout). No contradictions.

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 concise sentences, each adding essential information. First sentence states core purpose, second two provide usage guidance and behavioral context. No wasted words.

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?

No output schema, but description explains return format (base64) and side effect (saved file). Error conditions are documented. For a simple capture tool with good annotations and schema coverage, the description is complete.

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?

Only one parameter 'timeout' with full description in schema (100% coverage). Description mentions timeout in error context but does not add meaningful semantics beyond what the schema provides. Baseline 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?

Clearly states it captures a PNG screenshot of the running Godot viewport. The verb 'Capture' and noun 'screenshot' are specific, and the description distinguishes from siblings by mentioning use after simulate_input or run_script to verify visual changes.

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: use after simulate_input or run_script to verify visual changes, requires active runtime session. Does not explicitly state when not to use or compare to alternatives, but the guidance is sufficient for typical usage.

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