bulk_update_contacts

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

No annotations are provided, so the description carries the burden. It discloses the batch limit and that it updates contacts, but does not explain if the operation is idempotent, what happens on errors, or the return format (e.g., success response). This is adequate but minimal.

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 very concise with three short sentences. The first sentence clearly states the purpose. The inclusion of 'FREE' is extraneous but not harmful, keeping the overall structure clean.

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?

Given no output schema or annotations, the description is incomplete for a mutation tool. It lacks information about return values, error handling (e.g., partial failures), and any side effects. The 100-item limit is helpful but behavioral details are 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% (the array parameter has a description), so baseline is 3. The tool description adds 'Provide contact IDs and fields to update' which largely restates the schema, adding little new meaning.

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 clearly states 'Update multiple contacts at once' which distinguishes it from single-contact update tools like 'update_contact'. It also specifies the key inputs (contact IDs and fields), making the purpose clear.

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 mentions 'Max 100 per request' which gives a constraint, but does not provide guidance on when to use this tool versus alternatives like 'update_contact' for single updates. No when-not or explicit comparison is given.

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