activate_venv

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

With no annotations provided, the description carries the full burden. It discloses the non-obvious behavior that it is a session-level register, not a shell activation, and precisely states the effect on subsequent tool calls. It could add details about validation or persistence but is transparent about the core behavior.

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 two sentences, with the first sentence front-loading the core purpose and the second sentence adding a necessary distinction and the mechanism. Every word earns its place; no wasted text.

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?

This is a simple one-parameter tool with an output schema (per context signals), so return values need not be described. The description sufficiently covers what it does, what it doesn't do, and its effect on subsequent calls. It does not mention prerequisites like the venv existing, but the low complexity makes that omission acceptable.

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 schema already provides 100% coverage with a clear description for the single 'path' parameter (default '.venv'). The tool description adds no significant semantic information beyond the schema, so the baseline score of 3 applies.

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's purpose with a specific verb ('Register') and resource ('virtual environment'), and immediately distinguishes it from shell-level activation. It also differentiates from sibling tools like create_venv and deactivate_venv by specifying that it only records the path for subsequent python_* and pip_* calls.

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?

Provides clear context on when to use: before running python_* or pip_* tools so they use the venv interpreter/pip. It explicitly clarifies what it does NOT do (shell activation), which prevents misuse. It does not explicitly mention alternatives like deactivate_venv, but the context is sufficient for most agents.

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