Get Active Selection

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

With no annotations provided, the description carries the full burden of disclosing behavior. It clearly indicates this is a non-mutating read operation ('Read') and specifies the kinds of data returned (active object, selected objects, tag/material). It also mentions the crucial behavior of returning 'canonical handles' suitable for piping to other tools. It does not detail error cases or empty-selection handling, but the core behavioral traits are transparent.

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?

Three tight sentences: the first states the core function, the second explains the primary use case, and the third describes the output format and integration. There is no fluff or repetition; each sentence adds distinct value. The most important information is front-loaded.

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 there is no output schema and no annotations, the description adequately explains the main return contents (active object, all selected objects, active tag/material) and their nature (canonical handles). It does not specify the exact response structure or empty-selection behavior, but for a simple zero-parameter getter, this is reasonably complete for an agent to invoke and interpret the result.

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 input schema has zero parameters, so the schema itself is complete by definition. The description does not need to explain parameters. The baseline for 0 parameters is 4, and the description does not introduce any conflicting or missing parameter information.

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 uses a specific verb ('Read') and a precise resource ('the active document's current selection') with enumerated components: active object, all selected objects, and active tag/material. This clearly distinguishes it from sibling tools like set_selection, which mutates selection, and is far from tautological.

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 explicitly states when this tool is useful: 'reacting to the user's current focus without asking them to re-pick entities.' It also provides a workflow hint by noting that returned canonical handles can be piped into describe or set_params. It does not explicitly list exclusions or alternative tools, but the provided context is clear enough for an agent to select it appropriately.

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