read_url

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

With no annotations provided, the description carries the full burden and does so well. It discloses the stealth-browser behavior, hidden-text stripping with reporting in `threats`, and per-domain rate limiting. These are meaningful behavioral traits beyond what a schema could convey, making the tool's actions predictable.

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 three short paragraphs, each earning its place: first states the core function, second explains a key output feature and a primary use case, third provides sibling differentiation and a rate-limit caveat. It is front-loaded with the main verb and wastes no words.

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 that an output schema exists (so return values need not be explained) and the tool has 5 parameters, the description covers the essential operational context: stealth capability, anti-hiding behavior, alternatives, and rate limiting. There are no obvious gaps for an agent to invoke the 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 100%, so the baseline is 3. The description adds a little context (e.g., 'hidden text... stripped by default' relates to `include_hidden`, and 'URL you already have' reinforces `url`'s purpose), but it does not substantially enrich the parameter meaning beyond what the schema already provides. It is adequate but not exemplary.

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 opens with a specific verb+resource: 'Fetch one web page through the stealth browser and return clean, grounded content with provenance.' It clearly distinguishes itself from sibling tools by stating 'Reads a URL you already have: use `search` to find URLs, or `research` to search and read in one call.' This makes the tool's purpose unambiguous and immediately scoped.

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?

Usage is explicitly guided: 'Use this to ground answers in live web content, including sites that block plain fetchers.' It also names alternatives directly ('use `search` to find URLs, or `research` to search and read in one call') and warns about rate limiting ('Fetches are rate limited per domain (5s apart by default)'). This gives clear when-to-use and when-not-to-use context.

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