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

Adds substantial context beyond the annotations: the amount cannot exceed the remaining balance, a full-balance payment flips the invoice to Paid, autopay is unaffected, only manual payments are editable/deletable, per-call confirmation is default-on, the call reaches other people, and an API key with app access is required. This is rich mutation/effect disclosure.

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?

Dense with operational value and front-loaded with the core action, but the second sentence largely restates the first ('Log a payment received outside Dubsado...' / 'Logs a payment you received outside Dubsado...'), which is a redundant sentence that doesn't earn its place.

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 write tool with no output schema, it covers everything an agent needs: preconditions (amount limit, API key), side effects (invoice to Paid, autopay untouched), reversibility, and a confirmation/consent requirement. Nothing material is missing.

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%, so the schema already documents all five params (including the amount/remaining-balance constraint and method enum). The description adds the Paid-transition effect but no new per-parameter syntax or format detail. 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+resource+scope: logging an offline/manual payment against an invoice. The 'outside Dubsado, such as cash or a check' framing cleanly distinguishes it from dubsado_send_invoice, dubsado_create_invoice and any autopay path without needing to open the schema.

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?

Gives clear context for use (money received outside the system) and an implicit exclusion ('It does not cancel autopay'), but never names a sibling tool or states when to prefer dubsado_create_invoice/send_invoice instead. Good but not fully routing.

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