update_watchlist

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

Annotations already indicate idempotentHint=true and non-destructive/non-read-only nature. The description adds minimal context beyond 'modify'; it does not detail merge behavior or failure handling, but with annotations, the bar is lower.

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 concise sentence with no wasted words, including a helpful reminder that id is required. Ideal length for a simple update tool.

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?

The description is minimally complete for a mutation tool with annotations. It fails to specify whether partial updates merge or overwrite fields, the return format, or error handling. However, given the tool's simplicity and annotation coverage, it just meets adequacy.

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 only 25% (id has description). The description lists the modifiable fields (note, tags, display_name) but does not explain their semantics beyond that. Partially compensates for low schema coverage.

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 clearly states it modifies note, tags, or display_name of a watchlist item, with a specific verb and resource. It distinguishes from sibling tools like add_watchlist, list_watchlist, and remove_watchlist by specifying the update nature.

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 provides no guidance on when to use this tool versus alternatives, no prerequisites or exclusions, and does not mention that it requires an existing watchlist item.

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