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

Annotations provide readOnlyHint=false and destructiveHint=false, so the description isn't redundant. It adds useful behavioral context: the link is single-use, requires human authorization, and returns a connect_url. This goes beyond the annotations without contradicting them.

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 concise sentences, no fluff. The primary purpose and return value are front-loaded, and the alternative routing is placed second. Every word adds value.

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 create-intent tool, the description covers required information: allowed channels, default mode, return value, and an explicit alternative. It doesn't explain error conditions or prerequisites, but with an output schema existing and the operation being a straightforward link generation, it's sufficiently 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 0%, so the description must compensate. It does specify allowed values for channel (meta|google_ads|tiktok) and notes mode=add_connection, giving meaning to both params. However, it doesn't explain other possible modes or elaborate on the mode parameter beyond its default, leaving some semantic gaps.

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 the action: 'Create a single-use browser authorization link' and specifies the exact channels (meta, google_ads, tiktok) and mode (add_connection). It also names the return value (connect_url). This distinguishes it from sibling tools like setup_begin_channel_connect by explicitly naming the alternative.

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?

Provides explicit guidance: 'Prefer setup_begin_channel_connect when you need its explicit connect_id/check workflow.' This tells the agent when to use a different tool and implies when this one is appropriate (when a simple single-use link is needed). The context is clear and actionable.

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