sync_contacts_to_customers

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

The description discloses the core mutation behavior ('Creates or updates customer records'), which is the key side effect. It also adds workflow context beyond what schema hints provide. However, it does not mention idempotency, rate limits, or potential broad scope of sync, though the schema hints (idempotentHint=true) partially cover this. Without separate annotations, description carries the transparency burden, and it does so adequately for the main behavior.

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?

The description is concise, with the purpose in the first sentence and workflow in the second. No fluff, all sentences are informative and front-loaded.

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?

The tool is a data synchronization with no output schema. The description provides direction, timing, and follow-up steps, which is sufficient for a sync operation. It could mention potential edge cases or mapping details, but given the schema covers filters and the workspace is straightforward, the description is fairly complete.

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% for all 3 parameters, so the schema already documents source_module, target_module, and filters. The description adds no extra meaning to these parameters, only stating that records are created based on contact data. Baseline score of 3 applies because the schema handles parameter semantics.

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 states a specific verb ('sync'), resources ('CRM contacts', 'Books customers'), and direction ('CRM → Books direction'). It clearly distinguishes from sibling tools like sync_customers_to_contacts and sync_accounts_to_customers by making the one-way direction explicit.

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 description gives clear workflow context ('Typically run after CRM data updates') and a follow-up verification step ('Follow with books_get_customers to verify sync results'). It does not explicitly name alternative tools or say when not to use, but the context is sufficient for basic differentiation.

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