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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the safety profile is covered. The description adds that the tool returns a URL (OAuth URL), which is useful context beyond annotations. However, it does not disclose details like whether user interaction is required after obtaining the URL or how the result should be handled.

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 sentence of 9 words with no redundant information. It is front-loaded with the action ('Get the OAuth URL') and immediately clarifies the purpose ('to connect your Instagram account'). Every word earns its place.

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 tool with no parameters, no output schema, and minimal annotations, the description adequately explains the return value (an OAuth URL) and the intended action. It does not explain what to do with the URL, but for a connector tool this is likely self-evident. The description is complete enough for an agent to select and invoke it correctly.

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?

With zero parameters, the input schema is fully covered (100%). The baseline for 0 params is 4, and the description's mention of 'your Instagram account' adds no parameter-specific meaning but is not needed. No further explanation 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 the tool's function: 'Get the OAuth URL to connect your Instagram account.' It uses a specific verb ('Get') and resource ('OAuth URL') and explicitly mentions 'Instagram account,' distinguishing it from other connect_* tools for different platforms.

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 to obtain an OAuth URL for connecting Instagram. Sibling tools like connect_facebook or connect_twitter exist, but the description implies the use case without explicitly listing exclusions or alternatives. This meets the 'clear context, no exclusions' bar.

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