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

The description complements the readOnly and idempotent annotations by explaining what a journey contains and how parameters affect the selection. It does not contradict the annotations and adds useful context about the tool's behavior without needing to restate the obvious read-only nature.

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 succinct and well-structured, packing all necessary information into two sentences. It directly states what the tool returns and how to invoke it, with no redundant or confusing wording.

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 description fully explains the tool's output (a journey plan with its components) and the two usage modes, covering both parameters and the tool's behavior. Given the simple schema and no return schema, this is complete and self-contained.

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 schema already defines each parameter, but the description adds valuable meaning: it explains that 'slug' identifies a specific journey and 'goal' triggers an automatic selection. This clarifies the usage of both optional parameters beyond their basic type definitions, enriching the schema's coverage.

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 that this tool retrieves a guided journey, which is a phase plan with specific components (ordered skills, decision questions, docs file writes, go/no-go gates). It distinguishes from siblings like get_skill or search_skills by focusing on journeys, making its purpose unambiguous.

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 states when to use the tool: pass a slug for a known journey, or pass a goal to have one picked. This gives clear situational guidance, though it doesn't explicitly mention when not to use it in favor of alternatives, which is implicit from the sibling context.

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