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

With no annotations, the description carries the full burden and does well: it explains the session-based auth model (authorised once against a Trust-Score-derived limit, no per-call wallet signature), the refusal behavior without a session, and an output-side behavior (actionRequired 'deposit_required' plus a deposit object with checkoutUrl). It stops short of describing the receipt/ledger response or what happens on partial failure, so not a 5.

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?

Front-loaded with the purpose and the hard prerequisite, and each sentence carries actionable information. Minor waste in the editorial aside 'which is the entire point' and a slightly long final sentence, but overall tight for the amount of behavioral context it packs in.

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 mutation tool with 5 parameters, no annotations, and no output schema, the description covers the critical gaps: session prerequisite, action types, and the booking deposit return path. It could say more about the receipt returned and how spend affects the session limit over time, but an agent can call it correctly from this text.

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 the schema already documents amount-in-USDC, payload.businessId for bookings, sessionId provenance, and idempotencyKey retry semantics. The description largely restates the sessionId requirement and adds little parameter-level detail beyond what the schema provides, so baseline 3 is appropriate.

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 ('Spend against an open PabandiSession') and enumerates the three action types (book, pay invoice, fund escrow), which map directly to the actionType enum. It clearly distinguishes itself from pabandi_open_session and from the per-action siblings like pabandi_book_stay and pabandi_start_escrow.

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 states the prerequisite (REQUIRES a sessionId), names the alternative (call pabandi_open_session first and use its sessionId), and describes the failure mode if you skip it ('this tool will refuse without one rather than fall back to a per-call signature'). It also gives conditional guidance for the booking deposit flow.

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