list_vdi_sessions

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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered; the description adds genuinely new context by disclosing the return envelope ({items, returned, limit, total, truncated, hint}), the per-item fields, and the pagination/truncation behavior. It does not discuss rate limits or auth requirements, but for a read-only list tool this is solid added value.

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, front-loaded with the [READ] marker, scope, and filter axes before the return shape and the workflow hint. Every sentence carries information an agent needs; nothing is filler.

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, the description compensates by spelling out the return envelope, item fields, and truncation/hint semantics, and it covers filters, pagination, and the logoff/disconnect verification workflow. Nothing material is missing for correct invocation.

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 description coverage is 100% and each parameter already documents itself (exact pool id, substring user match, page size/offset, target). The description names the same filter dimensions without adding syntax or format detail beyond the schema, so baseline 3 applies.

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 and resource ('List Horizon VDI sessions') plus the three filter axes (user / pool id / state) and notes pagination. The plural 'sessions' plus filter scoping clearly separates it from the singular get_vdi_session sibling.

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?

Explicitly routes the agent: 'This is the verify pair for logoff/disconnect — get a session id or confirm a user's sessions here first.' That names the downstream tools and the reason to call this one first. It stops short of saying when NOT to use it (e.g., use get_vdi_session when the id is already known).

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