ghl_upsert_contact

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

With no annotations, the description carries the burden of disclosing behavior. It does state the core upsert behavior (create or update by email/phone), but omits important details such as matching precedence if both email and phone are provided, which fields get updated, and whether existing data can be overwritten.

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 two concise sentences that front-load the primary purpose and a secondary usage hint. Every word earns its place with no repetition or filler.

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 an 8-parameter tool with no annotations and no output schema, the description is quite sparse. It lacks information about return values, error behavior, or how the upsert handles conflicts, making it only minimally complete for real-world invocation.

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?

The description adds meaning to 'email' and 'phone' by identifying them as lookup keys, which is not in the schema. However, schema description coverage is 0% and the description ignores the other six parameters (tags, source, name fields, companyName, customFields), leaving their role ambiguous.

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 'Create or update a contact by email or phone,' which is a specific verb-resource pair with a precise matching mechanism. This distinguishes it from sibling tools like ghl_create_contact and ghl_update_contact by conveying the upsert semantics.

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 phrase 'Useful for ensuring no duplicates' provides a clear context for when to choose this tool over create or update. However, it does not explicitly state when not to use it or name alternatives, so it falls short of a 5.

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