Insert text at a character index

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

With no annotations, the description carries the full burden of explaining side effects, but it only states that text is inserted at a character index and cites the index source. It does not disclose what happens to existing text, whether an open document is required, whether the operation returns a result, or whether the change is destructive. This is thin behavioral coverage for a mutation tool.

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?

The description is a single front-loaded sentence that states the core operation and immediately adds the key source constraint in parentheses. Every phrase earns its place, and there is no redundant restatement of the title.

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?

The definition is minimally viable for a straightforward insertion call: it identifies the operation, the target resource, and the source of valid index values. However, it lacks guidance for choosing between insertion and append/set, does not define character-offset semantics, and provides no error or return context. With no annotations and no output schema, an agent still has to infer several important details.

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?

The schema already documents index and docIndex, and the description adds the useful fact that indexes come from the outline/scene tools. However, the required text parameter has no description in the schema and no description in the prose, leaving its semantics to be inferred from the tool name. The description only partially compensates for the schema coverage 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 description clearly states that the tool inserts text at a specific character index in a Beat document, and it tells the agent where valid indexes come from (beat_get_outline/beat_get_scenes). This makes the core operation unambiguous, but it never explicitly contrasts this tool with siblings like beat_append_text or beat_set_text, so it stops short of full sibling differentiation.

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?

The description gives a useful precondition — indexes come from beat_get_outline/beat_get_scenes — and the schema clarifies docIndex. However, it does not state when to choose this over beat_append_text or beat_set_text, nor does it provide 'use X instead' guidance. Usage is implied rather than explicit, so it does not fully satisfy the when-vs-alternatives requirement.

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