MCP Screen Text

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

No annotations are provided, so the description carries the full burden. While it describes the core operation, it lacks important behavioral details such as permissions needed, whether it requires user interaction, potential rate limits, error conditions, or what the output looks like (text format, confidence scores). For a tool with no annotation coverage, this is a significant gap.

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 perfectly concise with two sentences that each earn their place. The first sentence states the core purpose, and the second provides essential usage context about capture scope. No wasted words or redundancy.

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?

Given the complexity of a combined capture+OCR operation with no annotations and no output schema, the description is incomplete. It doesn't explain what the tool returns (text format, errors, or structure), system requirements, or behavioral constraints. For a tool with this functionality and zero structured coverage beyond inputs, more context is needed.

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 description coverage is 100%, so the schema fully documents all three parameters. The description adds no additional parameter semantics beyond what's in the schema (e.g., it doesn't explain the interaction between 'display' and 'applicationName' beyond what the schema already states). Baseline 3 is appropriate when the schema does the heavy lifting.

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's purpose with specific verbs ('captures' and 'extracts') and resources ('screenshot' and 'text'), distinguishing it from siblings like 'capture_screen' (only captures) and 'extract_text' (only extracts). It explicitly mentions the combined operation in one step.

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 provides clear context for when to use this tool (for combined screenshot and text extraction) and distinguishes between full screen vs. application window capture. However, it doesn't explicitly state when NOT to use it or name specific alternatives among the sibling tools (e.g., 'use capture_screen if you only need a screenshot').

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