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

Goes well beyond the annotations by disclosing concrete effects: no notification is sent to the tenant, no charge is attached, it executes without a confirmation prompt, and the resulting contact is deletable in DoorLoop. This is exactly the extra context needed for a write tool whose annotations only say readOnly=false and destructive=false.

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 core action well, but the 'no side effects' point is repeated three times ('Sends nothing' / 'it sends nothing to the tenant and attaches no charge' / 'it reaches no one'), and 'Adds one tenant contact' restates the opening sentence. Redundancy dilutes an otherwise efficient description.

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 simple create tool with full schema coverage and no output schema, the description covers everything an agent needs: what is created, the absence of external messaging or billing, the autonomy of execution, and the auth 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% and the four field names are self-explanatory, so the schema carries the parameter burden. The description adds nothing about format beyond the schema (e.g. the E.164 note lives only in the schema), so baseline 3 applies.

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 and resource ('Add a tenant contact') and scopes its downstream intent ('ready to put on a lease'), which cleanly separates it from doorloop_create_lease and doorloop_list_tenants. It stops short of naming an alternative explicitly, so it doesn't reach the sibling-routing level of a 5.

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?

Usage is implied by 'ready to put on a lease' – i.e. use this to onboard a contact before leasing – but there is no explicit when-to-use/when-not guidance and no named alternative for cases like adding a tenant that already exists. Adequate but with a clear gap.

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