read

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

With no annotations at all, the description carries the full burden and does disclose the key non-obvious behavior: silent auto-escalation to a headless browser when the plain read returns empty, plus a provider override that bypasses the default priority order. It omits failure semantics, timeouts, auth requirements, and any cost/latency implications of the browser escalation.

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?

Two tight sentences, front-loaded with the core action and output format before the edge cases. The pointer to usage(provider=…) replaces what would otherwise be a long enumeration of per-provider modes.

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 3-parameter read tool with no output schema and no annotations, the description covers output shape, escalation behavior, and provider selection adequately. The remaining gap is sibling disambiguation against 'browser', which matters because the description itself invokes headless browsing as an internal fallback.

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 coverage is 100%, so the baseline is 3 and the schema already documents url, mode, and provider. The description reinforces mode as a 'provider-specific escape hatch' and points to usage(provider=…) for the exact value set, which is helpful but largely duplicates the schema's own explanation.

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?

States a specific verb and resource ('Read a URL') plus the output form ('return its main content as clean markdown'), which is far more informative than the bare name 'read'. It does not differentiate itself from the overlapping 'browser' sibling or from 'search', so the reader must infer those boundaries.

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 implies usage (read a known URL; escalate automatically when plain read is empty) and routes the agent to usage(provider=…) for provider extras. However, it never says when to pick this over the 'browser' tool or when 'search' is the better starting point, and no exclusions are given.

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