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

Annotations already declare readOnlyHint=true, openWorldHint=true, idempotentHint=true, and destructiveHint=false, so the safety/read profile is fully covered. The description adds the 'cross-market' scoping and cursor pagination behavior, which is useful context beyond annotations. It doesn't disclose response format, but with an output schema present, that burden is reduced. Overall the description adds modest context on top of strong 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?

A single efficient sentence that captures the core action, scope, and pagination mechanism. Zero wasted words, front-loaded with the primary purpose. This is exemplary conciseness.

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?

This is a simple read-only list tool with 3 self-documenting parameters, a complete output schema, and strong annotations confirming safety. The description communicates the cross-market scope and pagination. Given the abundance of supporting structured data, the description is adequately complete — slightly shy of 5 only because it doesn't contrast with sibling news tools, which sibling disambiguation would require.

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 67% — the hours, limit, and cursor parameters are each described in the schema. The tool description itself adds essentially no parameter-specific meaning (it merely mentions cursor pagination generally). With moderate (67%) coverage, the description doesn't heavily compensate beyond what schema already documents, landing at baseline 3.

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 states 'Return recent cross-market news summaries' with a specific verb (return), resource (news summaries), and scoping ('cross-market', 'recent', pagination). It's clear about what it does. However, it doesn't explicitly distinguish from siblings like news_stock (per-stock news) or news_article, which would benefit from a brief contrast.

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 implies usage for fetching broad market news via the phrase 'cross-market', which hints it's the general option vs. news_stock being stock-specific. However, it never explicitly states when to use this vs. alternatives, nor mentions the cursor for pagination across multiple pages. No exclusions or when-not-to-use guidance is provided.

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