Get Active File

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

Annotations already convey read-only, non-destructive, idempotent, and open-world traits. The description adds value by noting the requirement for the Local REST API plugin and specific environment variables, and clarifies it targets the live Obsidian process unaffected by vault.select. This is helpful but could mention error cases (e.g., no active file).

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 concise with three sentences: first defines core functionality, second gives usage advice, third clarifies scope. No extraneous information.

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?

Given zero parameters, rich annotations, and an output schema, the description covers the essential information: what is returned, dependencies, usage context, and scope. It is sufficient for an agent to decide when and how to use this tool.

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?

There are no parameters, so baseline is 4. The description does not need to add parameter meaning.

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 returns information about the active file (path, modification time, edit/preview mode). It distinguishes itself from siblings by specifying it's read-only and used for orientation before workspace mutations, and clarifies it's not affected by vault.select, separating it from filesystem 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?

The description explicitly recommends using this tool to 'orient the agent before issuing other workspace-level mutations', providing clear context. However, it does not explicitly mention when not to use it or name alternatives, though the sibling list offers other workspace tools.

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