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

Annotations already flag non-readonly, destructive and non-idempotent behavior. The description adds genuinely useful context beyond them: the value is private and entered in BEON PASS rather than supplied by the caller, and an exact approval step gates the write. It still doesn't describe reversibility of overwriting an existing variable.

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, and the create/update purpose is front-loaded ahead of the approval constraint.

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 an 11-parameter tool with no output schema and no parameter documentation, the description covers the unusual secret/approval flow but leaves most of the schema opaque. An agent would still not know how to populate the beon_* fields.

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 description coverage is 0% across 11 parameters, so the description must carry the burden. It explains one key point (the value comes from BEON PASS, hence no value parameter), but the numerous beon_* parameters (beon_app_id, beon_context, beon_resume_id, beon_release_id, beon_environment, beon_connection_id) and the relationship of approval_id to the approval flow are left unexplained.

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 clear verb+resource ('Create or update an encrypted variable') with the scope of the operation. It doesn't explicitly name sibling tools like vercel_delete_environment_variable or vercel_list_environment_variables, but the create/update semantics are unambiguous.

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?

Conveys the precondition that exact user approval in BEON PASS is required, and implies create-vs-update behavior. However, it offers no guidance on when to prefer this tool over alternatives or what happens if the approval is missing.

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