Set Parameter

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

Annotations already declare destructive=true and idempotent=true; the description adds real behavior beyond them, explaining that dry_run executes and rolls back, that ambiguous matches are refused with candidate details, and that ambiguous document references are rejected before any change. Missing only auth/permission notes, so a 4.

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?

Front-loaded with the core action, then parameter-selection, value typing, dry_run and document semantics in efficient order. Dense but each line earns its place; slightly long but not padded.

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?

An output schema exists so return values needn't be detailed, and the description still references the verification block returned by dry_run. It covers selection, typing, units, and document targeting well for a destructive mutation tool; only failure/permission behavior is thin.

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 only 17%, so the description carries the burden and largely does: it explains parameter_id vs parameter resolution, the value typing rules (JSON string/integer/number), the unit conventions (mm, m2, internal units), and the dry_run/document flags. Only element_id is left implicit.

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 and scope: 'Set exactly one instance or type parameter.' That clearly separates it from mutation siblings like revit_move or revit_delete. It doesn't name or route away from any sibling, but the purpose is 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?

It gives concrete conditional guidance: use parameter_id to select by identifier vs a localized name when omitted, use dry_run to preview, and pass document only when multiple models are open. It stops short of explicit when-not-to-use or naming an alternative tool, so it's clear context rather than full routing.

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