Read

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

Annotations already cover read-only and open-world, so the description's job is to disclose mechanics — and it does: pagination via max_chars with each page ending in a continuation offset, plus the plain-text serialization (# headings, - items, | cells). Missing are edge behaviors such as cost of large pages or what happens with a stale/invalid ref.

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 sentences, front-loaded with the core action, then the format/paging contract, then the usage rule. Every clause carries information; nothing restates the name or annotations.

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?

With no output schema, the description correctly takes on the return-value burden by describing plain-text shape and the paging/continuation protocol. It stops short of saying how to recover from an invalid or stale ref, which is a minor residual gap for a 3-param read tool.

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, but the description adds real semantics beyond the schema: it explains that offset is the continuation token emitted at the end of each page and that max_chars governs page size — turning three bare fields into a coherent pagination loop.

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+resource ('Read a section's full text by its ref') and enumerates the section kinds it covers (paragraph, article, table, list, thread, main area). The trigger case 'where a view cut text short' makes it unmistakably different from scrolling or screenshotting.

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?

Explicitly instructs 'Use it to read long text instead of scrolling through it or taking screenshots of it', naming two alternatives and when to prefer this tool. It doesn't explicitly position itself against browser_find or browser_snapshot, which are the nearest siblings for locating vs. extracting content.

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