Edit root DOC fonts, metrics and encoded text

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

Annotations already declare this is a destructive, non-read-only, non-idempotent write, so the safety bar is partly met structurally. The description adds real behavioral context: it preserves electrical labels, shared definitions and opaque tails, states the encoding is exact/reversible for Chinese bytes, notes Chinese requires a Windows font, and recommends verifying glyphs in the original editor. It does not describe write ordering/failure behavior on a SHA mismatch, which keeps it from a 5.

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?

Four dense sentences, front-loaded with the scope/verb and then the encoding constraints; essentially no filler. Density of jargon makes it slightly harder to scan but every sentence carries 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?

For a complex, destructive, no-output-schema edit tool this covers scope, alternatives of font selection, encoding rules, preservation guarantees and a verification recommendation. Remaining gaps (error/precondition behavior around expectedSha256, relationship to gdf_text_format_inspect workflow) are minor given annotations cover the safety profile.

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 100%, so schema already documents syntax and defaults (baseline 3). The description adds cross-parameter meaning not present in the schema — that Chinese bytes in Windows-936 require a Windows font face — and reinforces width/height as explicit glyph/layout metrics rather than font size.

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 — 'Create/change only free root DOC text in GDF6 or standalone SYM2..6' — plus the font/metrics scope, which is more precise than the title alone. The scope restriction ('only free root DOC text', 'Preserves electrical labels...') helps separate it from broader edit tools, but it never names or contrasts with the close siblings gdf_text_edit and gdf_text_format_inspect.

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 through the scope constraint and the choices offered ('built-in font0..3 or Windows font face,size', 'Verify glyphs with original editor'), which tells the agent the intended operation shape. However, there is no explicit when-to-use vs gdf_text_edit / gdf_text_format_inspect guidance or prerequisite statement (e.g., run inspect first).

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