Close Active File

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

The annotations declare destructiveHint=false, but the description adds rich behavioral context beyond that: it documents the no-op behavior when no file is active, the return shape ('Returns { ok: true }'), the error condition (Local REST API plugin unreachable), and the vault targeting nuance. It also clarifies the operation is UI-only and does not persist changes. No contradiction with annotations.

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?

Every sentence carries real information: purpose, negative scope, no-op behavior, return/error contract, usage pairing, vault routing, and an example. The core statement is front-loaded, and the content is fully justified given the behavioral nuance of this UI-only mutation tool.

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?

An output schema exists to cover return values, and the description covers everything an agent needs: what it does, when to use it, what it doesn't do, the no-op case, error conditions, and vault targeting. For a zero-parameter tool this is complete with no gaps.

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?

This tool has zero parameters, so the baseline is 4. The schema is empty at 100% coverage, and the example shows an empty JSON invocation. Nothing more is needed since there are no parameters to document.

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 states the specific verb (close), resource (active file), and scope (in the Obsidian UI). It explicitly enumerates what it does NOT do ('does not delete, save, or modify file contents'), which cleanly distinguishes it from siblings like notes.delete and notes.edit. An agent can immediately tell this apart from the close-related and edit-related tools.

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?

Gives explicit when-to-use guidance: 'Use after workspace.openFile when you want to dismiss a temporarily-revealed note.' Also names the companion tool ('Pair with workspace.activeFile first if you need to know what was closed'), and clarifies it is not affected by vault.select. This is model guidance that routes the agent correctly.

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