Contacts: Create Contact

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

Annotations already declare the write profile (readOnlyHint=false, idempotentHint=false, openWorldHint=true, destructiveHint=false), so the safety bar is low. The description adds real value beyond that: the required auth header, the exact endpoint, and the note that text/IDs are sent unchanged and may contain Persian or Arabic-Indic digits. It does not say what happens on a duplicate email or identifier, which matters for a non-idempotent create.

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-loads the action and endpoint, then auth, then body fields -- a sensible order. The body-field list largely restates the schema, which is mild redundancy, but the added language/digit note justifies the length and nothing is padded.

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 10-parameter write tool with nested objects, no output schema and no idempotency guarantee, the description covers endpoint, auth, required fields, field list, the extra_body escape hatch, and input encoding. What it omits is failure/duplicate behavior and the distinction from the client-side sibling, which are the remaining reasons an agent could still mis-call it.

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 baseline is 3 and the schema already documents every field. The description earns above baseline by adding input-format nuance the schema omits: values pass through unchanged, and identifiers/phone numbers may use Persian or Arabic-Indic digits, which directly affects how a caller should format inbox_id and account_id.

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 ("Create a new contact in the account") and includes the endpoint, so the operation is unambiguous. However, it never distinguishes itself from the sibling gapify_client_create_contact, which addresses the same resource from a different API surface, so an agent cannot route between them from the description alone.

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 prerequisites (auth header, required inbox_id) but no when-to-use guidance and names no alternative. The critical ambiguity -- gapify_create_contact vs gapify_client_create_contact -- is left entirely unaddressed, and no note about duplicates or pre-checks is offered.

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