st.chat.variables.set

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

With no annotations, the description carries the full burden and does reveal the mutation behavior, storage location, and confirm requirement. It does not explain side effects such as snapshots, overwrite/force behavior, or the role of avatar/fileName, leaving important behavioral gaps for a 9-parameter write 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 two short sentences with no filler. The core action and the critical confirm requirement are placed up front, making the tool easy to scan.

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 tool with 9 parameters, 0% schema coverage, no annotations, and no output schema, the description only explains the basic action and one parameter. An agent cannot safely construct calls involving force, asJson, snapshotLabel, or fileName without additional external knowledge.

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 0% and the description only clarifies 'confirm' and the set/unset intent. The roles of force, value, asJson, avatar, fileName, and snapshotLabel are left entirely unexplained, so the description fails to compensate for the undocumented schema.

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 opens with a specific action, 'Set or unset', and names the exact resource: 'a local slash/macro variable stored in a specific chat's chat_metadata.variables'. This clearly distinguishes it from the sibling st.variables.set, which appears to be the non-chat-scoped variant.

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 provides a clear operational requirement ('Requires confirm: true') and implies the tool is scoped to chat-local variables. However, it never explicitly says when to prefer this over st.variables.set or st.chat.metadata.patch, nor does it state when not to use it.

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