Sibyl

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

With no annotations provided, the description carries the full burden of behavioral disclosure. While it mentions 'clean text content', it doesn't specify what 'clean' means (e.g., stripped HTML, no ads, formatted text), potential limitations (rate limits, authentication needs, URL restrictions), or error handling. The description provides basic functionality but lacks important operational context.

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 appropriately sized and front-loaded with the core functionality in the first sentence. The Args section is efficiently structured. While concise, it could potentially benefit from slightly more detail about what 'clean text content' entails, but overall it avoids unnecessary verbosity.

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 tool's moderate complexity (single parameter, no annotations, but with output schema), the description provides adequate but incomplete coverage. The presence of an output schema means the description doesn't need to explain return values, but it lacks important behavioral context about limitations, error conditions, and what constitutes 'clean' extraction. It meets minimum requirements but has clear gaps.

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 description explicitly documents the single parameter ('url: The URL to read') in the Args section, adding meaningful context beyond the schema's minimal coverage (0%). Since there's only one parameter and it's clearly explained in the description, this compensates well for the schema's lack of detail, though it doesn't provide format examples or validation rules.

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 specific action ('Read and extract clean text content') and resource ('from a URL'), making the purpose immediately understandable. It distinguishes this tool from sibling tools like 'analyze', 'chart', or 'research' by focusing on raw content extraction rather than analysis or processing.

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. While it's clear what the tool does, there's no mention of when it's appropriate (e.g., for web scraping, content summarization, or data extraction) or when other tools like 'research' or 'quick_search' might be better suited for different tasks.

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