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

Beyond the annotations, it discloses that no credits are spent, nothing is created, the planId expires in 24 hours and is single-use, and that the exact credit cost is returned and must be shown to the user. It also spells out the auth prerequisite with a setup URL and tells OAuth-aware clients to hand off to the authorization flow rather than asking for credentials.

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-loads the auth requirement, then purpose, then the elicitation script, then the return/handoff — a sensible order. It is somewhat bloated by reproducing the three questions verbatim when the schema already carries the identical text, which costs roughly a third of the length without new information.

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?

With no output schema, the description still specifies the return value (planId plus exact credit cost) and the planId's lifetime and single-use nature, plus the full pre/post condition chain. An agent has everything needed to call this and route the result correctly.

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 100%, so the per-parameter meaning is already documented; the description nonetheless adds the ordering constraint across the three required briefs and the instruction to ask the user verbatim rather than inventing a theme. That is real semantic guidance beyond the schema, though the question wording itself is duplicated rather than extended.

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 — "prices the pack's shared Style Sheet (design sheet)" — and explicitly contrasts with the write sibling by saying it happens "WITHOUT spending any credits or creating anything." An agent can tell this apart from create_design_sheet and from the rendering/approval steps without opening any schema.

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?

Gives an explicit position in the workflow ("The FIRST step for any new overlay pack"), the exact handoff ("then call create_design_sheet with this planId"), and the downstream blockers naming get_pack_status and approve_design_sheet. It also states a hard exclusion: scenes cannot be planned until the Style Sheet has rendered and been approved.

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