session_status

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered. The description adds non-obvious behavior beyond that: it is usable while an operation is blocked, and it lists the exact diagnostic fields returned, which matters because there is no output schema.

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?

Two short sentences, front-loaded with the verb and the report contents, followed by the one behavioral caveat that could change an agent's decision. No redundant restatement of the name or of the annotations.

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, enumerating the reported fields in the description is exactly the right compensation, and it does so. The only shortfall is that it does not indicate the shape/format of the report (structured object vs. formatted text), which an agent might want to know.

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 takes zero parameters, so there is nothing for the description to disambiguate; baseline 4 applies. The description correctly implies a no-argument call and spends its words on reported contents instead.

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?

States a specific verb ('Report') and resource ('the session'), then enumerates exactly what is reported: version, probe, license, CPU, target state, script depth, and directories. That enumeration makes it trivially distinguishable from session_open and session_close among its siblings.

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 clause 'Works while an operation is blocked' gives one genuine operational condition under which to reach for this tool, which is useful implied guidance. However, it never explicitly contrasts with siblings like operation_get (which also inspects operation state), nor states 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.