Scaffold Code Block

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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the safety profile is known, but the description still adds real behavioral detail beyond them: the tool writes nothing and must be followed by manual insertion, it normalizes visibility keywords against Flags, escapes the constant's Default value, and applies IDE-style indentation. It also defines failure modes (inapplicable argument for block_kind, non-identifier name, unescapable constant value), which no annotation covers.

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 purpose and the block-kind enumeration before the procedural insertion guidance, so an agent can stop reading early. It is dense rather than padded, though the clause about usage-guide.md Format Rules and placement before #tag ViewBehavior adds length that a pointer could have compressed.

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 it does so by stating the result is text only and describing what a control_event result contains. It stops short of showing the returned block's shape (headers, Flags line layout) or noting whether the text includes surrounding delimiters, which is the remaining gap for a text-generating tool.

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 would be 3; the description adds cross-parameter semantics the schema cannot express — that control_event yields an entire #tag Events block, and that only its inner Event/EndEvent portion should be pasted when one already exists, plus the general rule that arguments not applying to block_kind are errors. The individual per-parameter meanings still live in the schema rather than the description, keeping it below a 5.

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 description gives a specific verb ("Generates") plus a precisely enumerated resource: a #tag block for a .xojo_code or .xojo_window file, with the seven supported block kinds listed inline. An agent can distinguish it from siblings like edit_code or set_code because it is explicitly a text-generating, no-side-effect scaffolder rather than a file mutator.

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 states the use case explicitly (use instead of writing #tag syntax from memory when editing a project file on disk) and names the follow-up sibling, lint_project_file, for verification. It also states the exclusions: it only returns text, the caller must insert it, and it reads no files and needs no IDE — leaving nothing about when-to-use to inference.

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