st.extension.registry

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

With no annotations provided, the description itself must convey behavior. 'List' implies a read-only operation, and the description states what data is surfaced. However, it does not disclose anything about discovery behavior, failure modes, or whether any side effects occur, leaving some behavioral ambiguity.

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, focused sentence that front-loads the action and resource, then lists the specific information returned. Every phrase earns its place with no filler or repetition.

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 and no annotations, the description adequately names the return payload: enabled state, inferred extension_settings config keys, and current config. It is complete enough for an agent to understand what the tool provides, though it could add a note about error or edge-case behavior.

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 tool has zero parameters and the schema coverage is effectively 100% since no inputs are required. Per the baseline for parameterless tools, the description does not need to compensate, and it adds no irrelevant 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 ('List') with a clear resource ('discovered frontend extensions') and outlines the exact fields returned. It clearly differentiates from siblings like st.extension.install or st.extension.set_enabled by indicating this is a read-only registry inspection rather than a mutation.

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 verb 'List' implies this is the tool to use for inspecting discovered frontend extensions, but the description does not explicitly state when to prefer it over alternatives like st.plugin.registry or st.extension.configure. Usage context is implied, not spelled out.

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