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

Annotations already declare this is a write operation (readOnlyHint=false), not idempotent, and non-destructive, so the safety profile is covered. The description adds a useful behavioral distinction ('does not prove the flow works'), but does not mention side effects, approval requirements, or what the created journey contains.

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?

Three short sentences with no waste. The core purpose is front-loaded in the first sentence, and the next-step instruction follows logically.

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?

The tool has an output schema and full parameter descriptions, so return values and params are covered elsewhere. The description compensates by clarifying the tool's role (creating, not validating) and the follow-up action, leaving little missing for correct 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?

Schema description coverage is 100%, so the baseline is 3. The description adds the scoping constraint 'for an owned site' which loosely maps to siteId and startUrl origin requirements, but does not document prompt, frequency, or parameter interactions beyond what the schema explains.

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 and resource ('Save one customer goal', 'creates a learning journey'), and clarifies a scope constraint ('for an owned site'). It is distinguishable from siblings like add_site or add_check_in, but the repo-specific term 'learning journey' is not further defined for an agent unfamiliar with it.

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?

It explicitly tells the agent what to do next ('Call run_journey next to start the first private exploration'), which is strong sequencing guidance. It lacks explicit when-not-to-use guidance (e.g., versus update_journey or list_journeys), but the next-step instruction is concrete.

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