switch_profile

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 atomic writes to credentials.json::active, cache invalidation for clients in the process, and cross-process auto-sync via dispatcher mtime check (~10μs). This is rich, actionable behavioral detail beyond what structured fields could provide.

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 purpose is front-loaded in the first sentence and followed by high-value behavioral details. The version prefix '[Plugin v1.3.9]' is extraneous, and the CLI setup instructions are long, but they earn their place by guiding the agent on how to add profiles. Overall compact for the information conveyed.

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 moderate complexity of side effects (atomic file write, cache invalidation, cross-process sync) and the absence of annotations and output schema, the description is remarkably complete. It explains what happens, when, and even how to handle the related task of adding profiles, leaving no major gaps for an agent selecting and invoking 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?

The schema covers 100% of the parameter, including 'Use "default" for the primary profile' and source locations. The tool description adds no additional parameter-level semantics beyond the CLI examples for profile setup, which are tangential to the name parameter itself.

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 opens with a specific verb+resource: 'Switch the active identity profile.' This clearly distinguishes it from sibling tools like list_profiles and manage_profile_hints by focusing on the active profile switching operation, not listing or managing hints.

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 when to use the tool by stating it switches the active identity profile and separately instructs 'To add a new profile, run...', effectively telling the agent not to use this tool for adding profiles. However, it does not explicitly contrast with list_profiles or manage_profile_hints, so a clear alternative/exclusion is missing.

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