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

With no annotations, the description carries the full burden and does well: it discloses the no-op/idempotent short-circuit when a saved session is valid, that the viewer is not opened in that case, and that force_reconnect destroys the saved cookie. It does not say whether the call blocks while the user signs in or what a failure result looks like.

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?

Four short sentences, front-loaded with the default safe behavior, then the prerequisite, then the opt-in destructive path. Nothing extraneous; the repeated 'destructive' emphasis is proportionate to the risk.

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?

Covers the branching behavior, prerequisite, and risk for a one-parameter tool with no output schema. The only gap is what the tool returns or how long it blocks during interactive sign-in.

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 coverage is 100% and the single parameter is already well documented, so baseline is 3; the description adds a usage-level condition (only on explicit user request to sign out/reconnect/clear session) that reinforces the destructive semantics beyond the schema wording.

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?

States a specific verb and resource ('Open App Store Connect sign-in') plus the scope constraint ('only when needed'), and names the sibling that should gate it (session_status). An agent can distinguish it from login and session_status without further reading.

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?

Explicit ordering ('Call session_status first') and an explicit exclusion for the destructive path ('Use force_reconnect only when the user explicitly wants to wipe the saved cookie'). Both when-to-use and when-not-to-use are stated.

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