wafle_ads_creative_performance_log

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

Annotations already declare readOnlyHint=true and idempotentHint=true, covering the safety profile. The description adds meaningful behavioral context beyond annotations: the response includes 'fatigue_score' (0..1, higher = more fatigued) and 'phase' ∈ {learning, active, fatigued, off}. It also clarifies that the output is a row-per-day timeseries, which is not evident from the schema or annotations alone. It does not mention pagination or ordering, but that is minor given the read-only, idempotent annotations.

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 two short paragraphs, front-loaded with the core definition and then the use cases. Every sentence earns its place: the first sentence defines output structure, the second lists metrics, the third gives detection scenarios, and the fourth mentions additional response fields. No fluff or redundancy.

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?

Given there is no output schema, the description compensates well by listing all metrics (spend, impressions, clicks, conversions, revenue, roas, frequency, ctr, cpm) and the computed fields (fatigue_score, phase with its enum values). It also covers interpretation guidance. However, it does not specify row ordering, handling of days with no data, or any pagination/limit behavior, which leaves minor completeness gaps for a tool with 4 parameters and no output schema.

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 already fully documents all four parameters (slug, creative_id, since, until). The description does not add significant new semantics beyond what the schema provides—it merely repeats 'since' and the inclusive lower-bound concept. Baseline 3 is appropriate because the schema carries the parameter documentation burden.

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: 'Daily timeseries for a single creative_id since `since`.' This clearly defines the tool's scope (single creative, daily granularity) and distinguishes it from siblings like wafle_ads_breakdown_by_creative or wafle_ads_performance_summary, which likely operate on broader dimensions. The metric list (spend, impressions, clicks, conversions, revenue, roas, etc.) further specifies what the tool returns.

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?

The description provides explicit use cases: 'Use to detect (a) Learning Phase exit, (b) creative fatigue (frequency rising + CTR falling), (c) the right scale moment (3+ days of stable ROAS above target).' This tells an agent exactly when to invoke this tool. However, it does not mention when not to use it or suggest alternatives (e.g., wafle_ads_breakdown_by_creative for comparing creatives), so it stops short of a full 5.

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