Market overview

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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint, and destructiveHint=false, so the description only adds 'Read-only; not a recommendation.' This is a useful disclaimer but does not reveal additional behavioral traits such as data recency, source, or refresh behavior. No contradiction with annotations exists.

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?

Two short, purposeful lines. The core resource and output are front-loaded, and the disclaimer is kept separate. No filler or redundant restatement of the tool name.

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 simple read-only overview tool with one optional enum parameter, an output schema, and rich annotations, the description covers purpose, scope, and a caution. Nothing essential for an agent to select and invoke it correctly is missing.

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 input schema has 0% description coverage, but the only parameter is a self-explanatory enum with a default. The phrase 'period returns' hints that the period parameter controls the return horizon, adding some meaning beyond the schema, though it does not explain each enum value or default behavior in detail.

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 action and resource: 'Snapshot of major indexes, rates, dollar, gold, oil, BTC/ETH and EURUSD with period returns.' It clearly identifies the broad macro-market scope, which distinguishes it from siblings like search_markets, research_asset, and compare_assets that target narrower or comparative queries.

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 this is for a quick, broad market overview, but it does not explicitly say when to choose this tool over alternatives such as research_asset or compare_assets. There are no exclusions or when-not-to-use conditions, so the guidance is mostly inferred rather than stated.

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