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

Annotations already declare readOnlyHint=false, idempotentHint=true and destructiveHint=false, so the safety profile is covered. The description adds real value beyond that: it states 'Writes no journey and sends nothing', names the journeys_not_saved error route, instructs reuse of idempotency_key on retries, and notes the owner is notified afterward. It does not describe the response payload, but no output schema exists to cover that either.

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 core action is front-loaded, but the middle sentences are dense and parenthetical, packing field lists and source mappings into run-on clauses. Every sentence carries information, yet the structure could be tightened for easier parsing.

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 nested-object mutation with no output schema, the description covers the key gaps: the save-first prerequisite, the failure route, idempotency behavior, and the absence of side effects on journeys or messages. Only the return shape and the reason parameter's role are left implicit.

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?

With only 50% schema description coverage, the description compensates by enumerating the answers fields (firstChannel, speed, followUpChannel, tries, overDays, giveUpDays) and explaining that sources are the approved journeys mapped to lead sources such as site_thumbtack or web_form. The reason parameter is left to the schema, which documents it adequately.

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 opens with a specific verb and resource: 'Records the owner's approval of the lead journeys drafted from how the business follows up today.' That distinguishes it from siblings like edit_lead_step or redraft_lead_step, which modify journeys rather than approve them. It stops short of explicitly naming those siblings as alternatives.

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 gives a clear precondition: the journeys must already be saved via settings.lead_pursuit_program, otherwise the route answers journeys_not_saved. That tells the agent when the call will fail, but it does not explicitly contrast this tool with sibling approval or editing tools, so it falls short of full when/when-not guidance.

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