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

Annotations declare readOnlyHint=false and destructiveHint=false, so the mutation profile is already covered; the description adds the non-obvious piece that this changes session-wide context affecting every later editing call. It does not say what happens on an invalid or inaccessible id, nor whether the previous project state is preserved.

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?

Two short sentences with zero filler; the operation comes first and the persistent side effect second in a logical order.

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?

For a one-parameter, no-output tool this covers the essentials: the action and its lasting effect on other tools. Only minor gaps remain, such as id sourcing and error behavior on an unknown project.

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% for the single parameter, so the description carries the burden, and 'by id' confirms it is an identifier rather than a name or path. It gives no format or sourcing detail (where the id comes from, UUID vs numeric), leaving the agent to infer it from list_projects.

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?

States a specific verb and resource ('Switch to another project by id') and adds the consequence 'Every editing tool then works on it,' which separates it from read-only siblings like get_project or list_projects. It stops short of explicitly naming those alternatives.

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?

Implied usage is clear from the second sentence: call this before editing a different project so subsequent editing tools target it. There is no explicit when-not guidance, no mention of how to discover project ids, and no stated alternative such as create_project for nonexistent projects.

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