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

Goes beyond annotations by disclosing that a NEW design is returned with its own id, the original is preserved, and the call 'counts as one design' (a quota/billing implication). This is consistent with destructiveHint=false and idempotentHint=false and adds real value, though it says nothing about failures or limits.

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 tight sentences: the action and inputs come first, then the return/retention behavior and cost note. The inline examples earn their space and nothing is redundant.

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 carries the return-value burden and does so ('returns a new design with its own id'). Combined with full schema coverage, an agent has enough to call it correctly; only error/limit behavior is absent.

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 baseline is 3, but the description adds concrete instruction phrasing ('make the border gold', 'change TROOP 42 to TROOP 24') and restates the d_... id form, which clarifies the expected free-text semantics better than the schema alone.

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 (make a change) and resource (a design), plus the id format and the non-destructive copy behavior. It does not explicitly distinguish itself from the sibling design_patch, which is presumably the creation counterpart, so an agent must infer the division of labor.

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?

Usage is implied: pass a design id from an earlier turn and describe the change. The 'from this chat' scoping and the id-provenance note in the schema give useful context, but there is no explicit when-to-use vs. design_patch guidance or any exclusion.

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