split_contact_v1_enrich_split_contact_post

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

With no annotations at all, the description carries the full burden of behavioral disclosure. It adds one useful non-schema detail (billing context: 'Cost: 1 credit per request') and implies the output components, but it does not disclose error behavior, return format, or whether the operation is read-only or has side effects. Some value added, but significant gaps remain for an unannotated tool.

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?

Two tight sentences front-load the core action and output, with zero filler. The cost note is concise but slightly unconventional inside a tool description; it earns its place as useful billing context, so this rates just below a perfect 5.

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 single-parameter tool with 100% schema coverage and no output schema, the combination of description plus parameter guidance covers the essentials: what it does, what it produces, cost, and usage boundaries. Lacking is return-format detail and differentiation from the enrich_contact sibling, but complexity is low enough that this is not a critical gap.

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 schema parameter description already includes both semantic meaning and usage constraints, so the baseline of 3 applies. The description's list of output components adds marginal context beyond the schema but does not meaningfully compensate further.

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 states a specific verb (splits), the resource (messy contact string), and the structured output components (Name, Title, Phone, Email), making the tool's purpose clear. However, it does not distinguish this tool from its near-twin sibling enrich_contact_v1_enrich_contact_post — both appear to operate on contact data — so the 'distinguishes from siblings' bar for a 5 is not fully met.

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 parameter schema provides explicit guidance: 'USE THIS TOOL to extract structured components from a single line of contact info' and a NEGATIVE CONSTRAINT against paragraphs or multiple contacts, giving clear context and an exclusion. However, the description does not address when to prefer this over the similar enrich_contact sibling, so alternative-selection guidance is missing.

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