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

Annotations already declare readOnlyHint=true, openWorldHint=true, idempotentHint=true, and destructiveHint=false, which covers the safety profile. The description adds a minor behavioral detail (it returns an OAuth URL as part of the connection flow), but does not go into further depth such as whether the URL expires or requires user interaction. With annotations present, this is adequate but not rich.

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, focused sentence that immediately states the tool's purpose. It contains no extraneous words or repetition, making it highly effective for quick comprehension.

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 tool with no parameters and simple output (an OAuth URL), the description fully answers what the tool does and what the agent can expect. The annotations provide sufficient safety and side-effect context, so the description does not need to elaborate further. It is complete for its complexity level.

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 tool has zero parameters, so the baseline is 4, and schema coverage is 100% (vacuously). The description does not need to explain any parameters since none exist, and no additional semantic guidance is required.

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 a specific verb ('Get') and resource ('OAuth URL') for a specific target ('your Mastodon account'), which distinguishes it from sibling connect tools for other platforms. It goes beyond the title by specifying the exact output, making the tool's function 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?

The context is clear: this tool is used when a user wants to connect their Mastodon account, as evidenced by the name and description. It does not explicitly mention alternatives or exclusions, but the sibling list of platform-specific connect tools makes the intended usage obvious, so clear context with no exclusions merits a 4.

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