Delimit Cost Optimize

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

Annotations already declare readOnlyHint/idempotentHint/destructiveHint, and the description reinforces this in operational terms ('Side effects: read-only on the target'). It adds genuinely new behavioral context beyond annotations: the premium gating ('Gated by require_premium'), the exact unlicensed failure mode with the upgrade URL, that the call fails without running, and the internal backend routing ('Calls backends.tools_data.cost_optimize').

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?

Organized into labeled, scannable sections (When to use / When NOT to use / Sibling contrast / Side effects / Prerequisite) with the core purpose front-loaded. Every line carries distinct information; there is no filler or restatement of the title.

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?

Complete for a single-optional-parameter tool: purpose, use cases, exclusions, sibling differentiation, safety profile, licensing prerequisite, failure behavior, and backend identity are all covered. Return values are handled by the output schema, so no gap remains for an agent to invoke this correctly.

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 schema fully documents the single 'target' parameter (path, default '.'). The description adds no parameter-level detail beyond the schema's own description, so the baseline 3 applies.

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?

Opens with a specific verb+resource: 'Find cost optimization opportunities in a project (Pro).' The sibling contrast line ('delimit_cost_analyze identifies sources of cost; this proposes reductions') explicitly differentiates it from the nearest sibling, so an agent can distinguish it without opening schemas.

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?

Provides explicit when-to-use ('after delimit_cost_analyze surfaces drivers, to get concrete suggestions'), when-NOT-to-use ('to inventory current spend... or manage threshold alerts'), and names the alternatives (delimit_cost_analyze, delimit_cost_alert). The sequencing guidance ('after... surfaces drivers') is especially actionable.

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