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

With no annotations provided, the description carries the full behavioral burden. It usefully discloses that settlement is optional and that a settlement summary is returned, but it omits whether closing is irreversible, what happens to associated bookings or escrow, and what error conditions exist for an already-closed session.

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 with no filler, and the core action is front-loaded ahead of the optional behavior. Nothing is wasted, though it is arguably too terse given the mutation involved.

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 two-parameter mutating tool with no annotations and no output schema, the description covers the action and the return value at a high level. It still leaves gaps on irreversibility, failure modes, and downstream effects, which matter more here than for a read-only sibling.

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 100%, so both parameters are already documented. The description reinforces the `settle` flag's meaning ("optionally settle remaining funds") but adds no format or constraint detail beyond the schema's own text; 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?

The description names a specific verb and resource ("Close an open session") plus the optional settlement side effect, so the purpose is clear without opening the schema. It does not explicitly distinguish itself from siblings like pabandi_session_list or pabandi_cancel_booking, but the name-plus-description combination is unambiguous.

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?

"Close an open session" implies the session must be open, but the description states no preconditions, no guidance on when to use this versus pabandi_cancel_booking or pabandi_session_receipts, and no exclusions. An agent must infer usage entirely.

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