import_contacts

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

The description adds valuable behavioral context beyond the annotations: it discloses that existing addresses are updated rather than duplicated, and that per-row results are returned for rejected rows. This is significant because annotations are all false and provide no safety/intent hints. While not exhaustive, it meaningfully informs the agent of side effects and output expectations.

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 sentences, front-loaded with the primary purpose, and each sentence earns its place: action, update behavior, and output. No filler or repetition of schema details.

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?

Without an output schema, the description still explains the return value at a high level (per-row results with rejection reasons). It covers core invocation needs: bulk limit, update semantics, and feedback. It lacks some edge-case detail (e.g., behavior when update_existing=false), but is sufficient for an agent to select and call the tool correctly.

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% (both 'contacts' and 'update_existing' have descriptions), so the baseline is 3. The tool description reiterates the max-5000 limit and the update-existing behavior already present in the schema, adding no new parameter semantics beyond what is already structured.

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 opens with 'Bulk-import up to 5,000 contacts in one call,' which is a specific verb+resource statement that clearly distinguishes this tool from the sibling single-contact tools like create_contact and update_contact. The scope (bulk, max 5000) is 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 bulk-import framing conveys clear context for when to use this tool (large-scale contact imports). However, it does not explicitly name alternatives or state when not to use it (e.g., for single contacts). This is clear context without explicit exclusions.

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