STRING-MCP

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

With no annotations provided, the description carries full burden for behavioral disclosure but offers minimal information. It states the tool returns a URL but doesn't describe what happens with that URL, whether the image is generated dynamically or cached, any rate limits, authentication requirements, or error conditions. For a tool with 10 parameters and no annotation coverage, this leaves significant behavioral gaps.

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 at just 5 words: 'Return URL of STRING network image.' Every word earns its place by specifying the action, output format, and resource type. There's zero waste or redundancy, and the core purpose is communicated immediately without unnecessary elaboration.

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 complex tool with 10 parameters, no annotations, and no output schema, the description is insufficiently complete. It doesn't explain what a 'STRING network image' represents visually, how the URL can be used, what format the image returns in (beyond SVG parameter), or any limitations of the service. The agent must rely entirely on parameter schemas without contextual understanding of the tool's behavior and outputs.

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 already documents all 10 parameters thoroughly with descriptions, enums, and defaults. The description adds no parameter-specific information beyond what's in the schema. According to scoring rules, when schema coverage is high (>80%), the baseline is 3 even with no param info in the description.

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: 'Return URL of STRING network image' specifies both the verb ('return URL') and the resource ('STRING network image'). It distinguishes from siblings like 'get_enrichment_figure' or 'get_network_interactions' by focusing specifically on image generation rather than data retrieval or analysis. However, it doesn't explicitly differentiate from potential image-related siblings beyond the STRING context.

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 no guidance on when to use this tool versus alternatives. It doesn't mention when this image generation tool should be preferred over data-focused siblings like 'get_network_interactions' or 'get_interaction_partners', nor does it specify prerequisites or contextual constraints. The agent must infer usage from the tool name and parameters alone.

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