Save a printer profile

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

Annotations flag the write and its destructiveness but say nothing about blast radius; the description supplies that (only `topopt-printers.yaml` is touched, other entries stay). It also discloses idempotent replacement ('the same id replaces a user entry'), refusal rules for shipped ids/aliases, validation against the shipped-catalog rules, and the no-write failure mode — all consistent with destructiveHint=true and idempotentHint=true.

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 action and write target, then usage sequence, then field spec, then return/error behavior — a sensible order. It is dense and long for a one-parameter tool, but the length is mostly justified by the undocumented profile schema; a few lines (e.g. 'There is no CLI command: edit the file.') are instructional plumbing rather than tool behavior.

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?

Given one nested free-form object, no output schema, and mutation semantics, the description covers everything an agent needs: preconditions, per-field validation, collision/refusal behavior, the returned fields (ok, path, profile, created, replaced, note, problems), and the two failure modes (bad argument, invalid YAML) with the guarantee that nothing is written.

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% and the single `profile` parameter is a free-form object with no documented properties, so the description carries the entire burden — and does: required keys with formats (id slug, printer_type enum, bed_mm as [x,y], source_url or 'user'), the full optional set with value constraints ('heated'-only chamber_max_c, nozzle material enum), and null-means-unknown semantics plus field_sources.

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: keep a printer that is not in the catalog, into `topopt-printers.yaml` in the work folder. It also scopes itself ('It writes only that file') and implicitly separates itself from `find_printer` (the lookup it follows) and `save_material` (a different file).

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?

Explicit trigger and sequence: use it after `find_printer` says 'none', look up the maker page, show the user the values with the page address, and call only after the user agrees. It also states the negative rule for missing values (stay null, ask, do not guess).

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