create-highlight

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

Annotations already indicate readOnlyHint=false and destructiveHint=false, so the write-but-not-destructive behavior is clear. The description adds the useful context that the highlight is placed using character offsets from readable content, but does not disclose edge cases like invalid offsets or whether the operation can fail.

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 a single, well-structured sentence that is front-loaded with the action and includes the essential mechanism. Every word contributes to understanding the tool's purpose and input requirements.

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 create tool, the description combined with the complete parameter schema and annotations provides sufficient context for an agent to select and invoke it. It does not describe the return value, but no output schema exists, and this is a common gap that does not detract heavily from the tool's usability.

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?

The input schema already provides detailed descriptions for all 6 parameters (100% coverage). The description adds semantic value by clarifying that startOffset and endOffset refer to positions in the bookmark's readable content, which is not explicitly stated in the schema itself.

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 uses a specific verb ('Create') and resource ('a text highlight on a bookmark'), and further specifies the method ('using character offsets from the bookmark's readable content'). This clearly distinguishes it from sibling tools like get-highlight, update-highlight, and delete-highlight.

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 the tool should be used when creating a text highlight, and provides context that offsets must come from the bookmark's readable content. However, it does not explicitly state when to prefer this tool over alternatives or mention any exclusions.

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