trigger_journey

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

Annotations already declare readOnlyHint=false and destructiveHint=true, so the agent knows this is a mutating operation. The description adds that it returns an enrollment_id for polling, which is genuinely useful, but it omits other behavior: whether re-enrolling is idempotent, what metadata does, and that the operation sends real WhatsApp messages to a live contact.

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 tightly written sentences with zero filler; the primary action and the return contract are both front-loaded. Nothing could be cut without losing information.

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?

With no output schema, the description correctly states the return value (enrollment_id), which is the key missing piece. However, for a 5-param destructive mutation it does not explain idempotency semantics, metadata propagation, or what happens on duplicate enrollment, so an agent still has open questions.

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 coverage is 0% across 5 parameters, so the description carries the full burden but only clarifies that trigger_name and journey_id are alternative selectors. It says nothing about metadata, idempotency_key, or the phone format constraints, leaving the two most behaviorally significant optional params undocumented.

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 gives a specific verb (enroll) and resource (one phone number in a WhatsApp journey), which is more precise than the tool name alone. It implicitly distinguishes itself from trigger_journey_batch by emphasizing a single number and from validate_journey_trigger by implying actual enrollment, though neither sibling is named.

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 only implied through the name and the 'one phone number' phrasing; there is no explicit when-to-use or when-not statement. It does hint that enrollment_id can be used with check_journey_status, which is a useful breadcrumb but not a routing rule.

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