Katzilla MCP

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

The description adds significant behavioral context beyond annotations: it details security restrictions (blocks private addresses), performance limits (5 MB cap, 5 redirects), data processing (HTML to plain text), and output format (Katzilla envelope with quality/citation details). Annotations cover read-only, non-destructive, idempotent, and open-world hints, but the description enriches this with operational specifics without contradiction.

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 front-loaded with core functionality, followed by behavioral details and usage intent, all in two dense but efficient sentences with zero waste—every phrase adds necessary information without 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 tool's complexity (fetching URLs with security and processing), rich annotations, 100% schema coverage, and an output schema (implied by describing the return format), the description is complete: it covers purpose, usage, behavior, and output without needing to repeat structured data, making it fully adequate for agent use.

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?

With 100% schema description coverage, the baseline is 3, but the description adds value by clarifying parameter semantics: it implies the 'url' parameter must be public and not blocked, and it explains the 'format' parameter's effect ('converts HTML to plain text' vs. 'raw'), though it doesn't detail 'timeoutMs' beyond the schema. This elevates it above the minimum.

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 ('fetch', 'return') and resources ('public http(s) URL', 'body as text'), and distinguishes it from siblings by emphasizing its general-purpose page reader role for AI agents, unlike the other utilities tools (e.g., qr-code, url-shortener) which serve different functions.

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?

It explicitly states when to use ('Intended as a general-purpose page reader for AI agents') and provides clear exclusions ('Blocks private/loopback/link-local/metadata addresses'), with implied alternatives for non-public URLs or other utilities tools, though no specific sibling tool is named for direct comparison.

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