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

No annotations are supplied, so the description carries the full disclosure burden. It never says whether the crawl is asynchronous, whether it fails on unreachable or duplicate URLs, what permissions are required, or whether adding a source is reversible — all critical for a mutation tool.

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?

A single front-loaded sentence with no filler; the action and its downstream effect are stated up front. Nothing can be trimmed without losing information.

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 simple two-parameter mutation with no output schema, the description states what happens at a high level, but given zero annotations and an undocumented url parameter, it leaves the asynchronous indexing behavior and error conditions unexplained. It is minimally viable rather than complete.

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 50%: workspace_id is documented as a UUID, but url has no schema description. The phrase 'for crawling and indexing' hints that url is fetched and indexed, yet the description adds no format, validation, or duplicate-handling meaning beyond that.

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 and resource ('Add a URL source to a workspace') and adds scope ('for crawling and indexing'), which distinguishes it from sibling upload tools like create_upload. It stops short of differentiating further, but the core action is unambiguous.

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?

There is no guidance on when to use this versus the upload or other source-adding siblings, nor any stated prerequisites such as the caller needing write access to the workspace or the URL being publicly reachable. The agent must infer everything about selection conditions.

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