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

With no annotations, the description carries the full burden and largely succeeds: it discloses the paid model (x402, $0.02 USDC per call), the settlement proof artifact (ProofOfSettledOutcome, kind 30120), and the no-charge refusal condition when sources can't be fetched. It is docked for the duplicated, garbled refusal sentence rather than a single clear failure-mode statement.

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 opening is well front-loaded with the core capability and pricing, but the description repeats the same refusal rule twice in near-identical, awkwardly worded sentences ('Refuses, with no charge, when ≥3 fetched web sources cannot be fetched' vs. '...when the required source (≥3 fetched web sources) cannot be fetched'), which adds noise rather than information.

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 single-parameter tool with no output schema and no annotations, the description covers the important agent-facing facts: cost model, settlement artifact, failure/refund behavior, and tier positioning versus the deep researcher. What is missing is a mention of the shape/timing of returned items, but the core call-time decisions are covered.

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 tool has a single 'task' parameter and schema description coverage is 100%, so the schema already documents it fully. The description adds no syntax, format, or constraint guidance for 'task' beyond what the schema provides, which is the baseline 3 case when the schema does the heavy lifting.

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?

States a specific verb + resource ('Fast real-time news scan across 44+ curated domains') and adds scope ('every item source-attributed'). It explicitly positions itself against a named sibling, research.topic-deep-researcher, as the 'quick-scan tier', so an agent can distinguish them without opening either schema.

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?

Names the alternative (research.topic-deep-researcher) and gives the selection criterion implicitly: this is the fast quick-scan, the other is the slower citation-grade report. That is a clear context signal, but there is no explicit 'use this when / avoid when' phrasing or list of prerequisites for choosing this tier.

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