control_center

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the description adds real value by disclosing that the tool launches a browser UI and that 'the link is never shown here' — output behavior the agent could not infer from the annotations or empty schema. The qualifier 'On this computer' hints at environment-dependent behavior without clarifying what happens elsewhere, which is the only gap.

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?

Purpose is front-loaded in the first clause, and the second sentence carries the one behavioral fact that matters most (browser launch, no link returned). The parenthetical enumeration is dense but each item earns its place by mapping to a sibling tool; slightly long but not padded.

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?

With no parameters, an output schema present, and annotations covering the safety profile, the description supplies what remains: what the control center contains and that it opens in the user's browser. The only unresolved ambiguity is the 'On this computer' scoping, which leaves the remote/non-local case unstated.

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 takes zero parameters, so the baseline of 4 applies; there is nothing for the description to disambiguate and it does not mislead about inputs.

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+resource ('Open the Encryptor MCP control center for the user') and then enumerates the capabilities it exposes (vaults, undo, trash, settings). An agent can distinguish it from siblings like 'unlock', 'undo', and 'trash_list' because those are named as things living inside the control center rather than competing actions.

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 description implies the routing rule: the sibling operations (unlock, lock, undo, trash, settings) can be surfaced to the user through this control center, and 'opens in the user's own browser' signals a user-facing handoff rather than an AI-executed action. It never states an explicit when-to-use/when-not clause, so it stops short of a 5.

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