Read a web page

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

Annotations already declare readOnlyHint, openWorldHint, and idempotentHint, and the description contradicts none of them. Beyond that, it adds three substantive behavioral facts: the tool runs a real browser so JS rendering works, it starts no browser session so there is nothing to release, and it always returns page links and metadata alongside content. This is solid context beyond the annotations, though it stops short of disclosing failure behavior or rate limits.

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?

Four sentences with zero waste: purpose and capability, session lifecycle, return-value behavior, and usage routing each get one sentence. The core action is front-loaded in the first line, and every sentence earns its place.

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 tool with one required parameter, a fully covered schema, and rich annotations, the description covers selection criteria, session handling, and return basics. Since there is no output schema, the return structure is only sketched as 'links and metadata,' but the combination of a 100%-covered schema, strong annotations, and this description leaves no critical gap for correct selection and invocation.

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 all six parameters are already fully documented in the schema. The description adds only marginal parameter-level meaning (markdown/HTML correspond to the format parameter, and 'no browser session' explains why no session parameter exists). Baseline 3 is appropriate since the schema does the heavy lifting.

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 action — 'Read a web page as markdown or HTML through a real browser' — and adds distinguishing capability detail: it handles JavaScript-rendered pages and sites that block plain HTTP fetches. An agent can clearly tell this apart from steel_screenshot, steel_pdf, and steel_session_create without opening their schemas.

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 last sentence is an explicit routing directive: 'Use this first for anything you only need to read; reach for steel_session_create only when you need to click, type or move through several pages.' It names the alternative tool and the exact condition that selects it, leaving nothing to inference.

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