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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive behavior. The description adds valuable behavioral details beyond those: line-numbered output, a ~250-line limit per call, and 1-based inclusive start/end semantics. This is meaningful supplementary information.

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 dense sentences convey action, output shape, range syntax, line limit, and an efficiency tip without filler. The structure is front-loaded and every phrase 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 low-complexity read tool with a rich output schema and safety annotations, the description covers the essential operational concerns: path examples, line cap, range semantics, and grep-first advice. A minor gap is not stating what happens if a range is omitted or if a file exceeds the line limit without a range.

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 carries the burden. It explicitly explains start_line/end_line as a 1-based inclusive range, but the path parameter is only illustrated with examples rather than formally specified. The default behavior when start_line/end_line are omitted is also left implicit.

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 pair, 'Read a workspace file with line numbers,' and reinforces it with concrete path examples. This clearly differentiates ws_read from its write/sibling tools like ws_edit, ws_grep, and ws_ls.

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 gives practical context: use it for reading specific workspace files, and 'Grep first on long files' explicitly steers agents toward the grep alternative for lengthy content. It does not enumerate exclusions for all siblings, but the read-only intent and line-range usage are clear enough.

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