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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so the safety profile is covered. The description adds genuinely non-redundant context: the result is an AI synthesis of multiple real-time sources (freshness/aggregation behavior) and a $0.25 USDC x402 cost, which matters for an agent deciding whether to call it. It does not describe result shape or latency, keeping it below a 5.

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?

Three compact sentences: what it returns, when to use it, then cost. Zero filler and the payload description is front-loaded ahead of the commercial detail.

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 one-parameter read tool with rich annotations, the description covers output nature, sourcing model, use cases, and the paid-call cost. No output schema exists, but framing the return value as an 'AI-powered summary' is sufficient for correct invocation.

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?

Single parameter with 100% schema description coverage, so the schema already explains that 'lookup' is a company name or topic. The description's phrase 'a company or topic' echoes the schema rather than extending it (no guidance on ticker vs. legal name vs. free-form topic breadth), 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?

States a specific verb and resource: an AI-generated summary of recent news for a company or topic, sourced from multiple real-time sources. It is clearly distinguishable in substance from siblings like interzoid_buying_signals or interzoid_x_last_three_posts, but it never names an alternative, so the agent must infer the routing itself.

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?

Four concrete scenarios (account research, sales triggers, competitive monitoring, market intelligence) give an agent a clear sense of fit. There are no exclusion conditions or named sibling alternatives, so it stops short of full routing guidance.

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