femm_save_bitmap

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

With no annotations, the description carries the full burden and does well: it discloses the headless no-op behavior, that view='pre' after a solve switches window focus, and that unset plot_type/lower/upper fall back to FEMM's auto-scaled default. It does not mention overwrite behavior for an existing path or what is returned on success/failure.

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?

Purpose and the critical headless caveat are front-loaded, and the parameter notes are packed densely with no filler sentences. The parenthetical enumerations of plot_type numeric codes are verbose but carry real information, so it stays on the right side of the conciseness line.

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, no-output-schema, no-annotation tool this covers nearly everything an agent needs to call it correctly and avoid the headless trap. The remaining omissions (path resolution, session, legend/grayscale toggles) are minor against the depth of what is provided.

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% and there are 11 parameters, so the description must compensate — and it explains the hard ones well: view semantics (post=solution plot, pre=geometry), the density/plot_type value encodings per physics type, the interaction that an explicit plot_type requires lower/upper, contours, and zoom format. It leaves legend, grayscale, session, and path undocumented, which is a modest but real gap.

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 first sentence states a concrete verb+resource (screenshot of the current view to an image file) and even names the underlying FEMM commands (xo_savebitmap / xi_savebitmap) plus supported formats. It is clearly distinguished from siblings like femm_export_dxf (vector geometry export) and femm_make_plot (headless data plots).

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 an explicit precondition — 'VERIFIED: works only in a session opened with femm_session_open(headless=False)' — and states the failure mode (headless accepts but writes nothing). It also names the alternatives for the headless case: 'For data plots that work headless use femm_make_plot or femm_mesh_arrays.'

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