workspace_open

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

readOnlyHint=true and destructiveHint=false already communicate safety, and the description adds meaningful behavioral context: this is not a sandbox, and absolute and parent paths remain usable. It also discloses what the tool returns, going beyond the annotations. No contradiction with the annotations is present.

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?

Three dense, load-bearing sentences with no filler. The primary action and return values are front-loaded, the parameter default is stated compactly, and the sandbox clarification earns its place by forestalling a common misconception.

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 the tool's low complexity, one optional parameter, and no output schema, the description is nearly complete: it covers the parameter, the default, path behavior, and return contents. It could add error conditions or post-open expectations, but nothing required for a correct call is missing.

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 0%, so the description must explain cwd, and it does: it defines it as a local working directory, states the default behavior when omitted, and clarifies that absolute and parent paths remain usable. It does not go into relative-path details, but for a single optional parameter this is sufficient.

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 names a specific verb and resource ('Open a local working directory') and enumerates the concrete return payload (workspace_id, account, Git state, instructions, skills). The 'directory routing, not a sandbox' clarification further distinguishes it from container-like or command-execution 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?

It gives a clear usage rule ('Omit cwd for home') and states that this is directory routing, but it never explicitly says when to prefer this tool over siblings like read, ls, or workspace_close. The intended usage is implied rather than stated as a decision rule, and no alternatives are named.

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