spot_price_history

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It effectively describes authentication requirements ('Requires Azure authentication'), data scope ('Returns up to 90 days'), and the specific data type ('Spot pricing data'). It doesn't mention rate limits, error conditions, or response format details, but covers the essential operational context well.

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 perfectly concise with three tightly-packed sentences that each serve a distinct purpose: stating the tool's function, specifying authentication requirements, and defining the data scope. Every word earns its place with zero redundancy or unnecessary elaboration.

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 read-only data retrieval tool with 3 parameters and 100% schema coverage but no output schema, the description provides good context about authentication, data type, and temporal scope. It could be more complete by describing the response format or data structure, but covers the essential operational context adequately given the tool's complexity.

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 schema description coverage is 100%, with all parameters well-documented in the schema. The description adds minimal value beyond the schema by mentioning that parameters are for 'a specific SKU and region' and implying 'os_type' through context, but doesn't provide additional semantic context or usage examples beyond what's already in the structured schema.

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 clearly states the specific action ('Get Spot VM price history'), resource ('for a specific SKU and region'), and scope ('up to 90 days of historical Spot pricing data'). It distinguishes from siblings like 'azure_price_search' or 'azure_price_compare' by focusing specifically on historical Spot pricing data rather than current pricing or comparisons.

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 context by specifying 'Requires Azure authentication' and the data type ('Spot VM price history'), but doesn't explicitly state when to use this tool versus alternatives like 'azure_price_search' or 'spot_eviction_rates'. It provides authentication prerequisites but no comparative guidance on tool selection.

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