session_close

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

With no annotations, the description carries the full burden, but it does disclose the concrete effect: the owned viewer and model worker are terminated. It does not say whether the close is idempotent, whether it releases server-side state, or whether it requires ownership/permissions beyond the word 'owned'.

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?

A single front-loaded sentence with no filler, stating the action and its scope immediately. It is appropriately sized for a simple teardown tool, though it is perhaps too terse given the gaps elsewhere.

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?

An output schema exists, so return values need not be explained, and the one-parameter surface is small. However, for a destructive mutation with no annotations, the description omits preconditions, side effects on related state, and parameter provenance, leaving meaningful gaps.

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?

One required parameter with 0% schema coverage, so the description must compensate and it does not – session_id's format, origin (from session_create/session_status), or validity conditions are never described. The term 'session' only loosely ties the parameter to the tool.

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 (close) and names the two resources torn down (owned viewer and model worker), which is more informative than 'close a session'. It stops short of distinguishing itself from the sibling view_close, which an agent could easily confuse it with.

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?

There is no statement of when to use this tool versus view_close or when session teardown is appropriate (e.g., after a job completes). Nothing tells the agent about preconditions or the alternative of closing only the viewer.

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