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

Annotations already declare readOnlyHint=true, non-destructive, and closed-world, so safety is covered structurally. The description adds the useful behavioral fact that this is a UI-internal helper, but it says nothing about what the call returns or why provider/resume_token exist, and an output schema exists so return detail is partly excused.

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 short sentences, no filler, and the most important constraint (do not call) is stated immediately after the one-line identity. Nothing needs trimming.

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 deliberately non-agent-facing helper the description does the minimum: it warns the model away and an output schema exists. However, it leaves the agent with no fallback instruction about which sibling to use for connection checks, which matters given the crowded sibling set.

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% for two parameters (provider, resume_token), so the description carries the full burden and adds nothing at all about either. The agent cannot tell what values are valid or how resume_token relates to provider.

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?

"Private MCP Apps connection-card helper" identifies a resource area and hints at a UI-side role, but it never says what the tool actually does (check a provider connection? return a card?), so the verb is missing. The critical scoping line, that models must not call it, is clear, but the operational purpose is only implied.

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?

It gives an explicit and unambiguous when-not: "Models must never call this tool directly." That is strong routing guidance. It does not name what an agent should use instead among the siblings (connect_source, disconnect_source, resume_question), which keeps it from a 5.

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