fetch_page

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

With no annotations, the description carries the burden and does well: it discloses the 24-hour cache, the article_only fallback behavior with Trafilatura, and the delta marker behavior for unchanged content. It could also mention max_chars truncation or error behavior, but the main behavioral traits are covered.

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 information-dense but tightly organized: main behavior up front, then parameter flags, then clear when/not-when guidance. No filler sentences; each clause adds actionable value.

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 4-parameter fetch tool with no annotations but an output schema, the description provides strong context: cache, delta behavior, article mode, and routing to sibling tools. The only minor gap is the lack of explicit max_chars semantics, but overall the agent has enough context to call this tool correctly.

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 0%, so the description compensates by explaining article_only and delta in meaningful terms. url is self-evident and max_chars, while not explicitly defined, has a name that makes its purpose clear enough.

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 what the tool does: return page text stripped of HTML clutter, suitable for articles, docs, and READMEs. It also distinguishes itself from related tools by naming batch_fetch, extract, and session_start as alternatives.

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?

Explicit WHEN and NOT WHEN sections list concrete conditions: use for a single page even JS/SPA, use batch_fetch for 10+ pages, extract for schema-based fields, and session_start for clicks/input. This leaves no ambiguity about when to choose this tool.

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