Historical electricity prices between two ISO 8601 dates (inclusive range as implemented by the API). Use for backtesting, charts, or ‘what did power cost last week?’. Requires API plan that allows /v1/prices/history in production.
| Name | Required | Description | Default |
|---|---|---|---|
| to | Yes | Range end as ISO date or datetime inclusive. | |
| from | Yes | Range start as ISO date or datetime (e.g. 2025-01-01 or full ISO8601). | |
| zone | Yes | Bidding zone code. |
Changes observed during successful MCP inspections. Dates show when Glama detected each change.
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden. It discloses the inclusive-range API behavior and the production API plan requirement, which is useful. However, it does not describe the response format, pagination, rate limits, or explicitly state that it is a read-only operation. For a data retrieval tool, this is adequate but not rich.
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 sentences, front-loaded with the core function, followed by use cases and a requirement. No wasted words. Every sentence adds value.
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 3-parameter historical price tool with no output schema, the description covers purpose, usage, and a key prerequisite. It lacks detail on the return shape or error behavior, but given the simplicity and the presence of sibling tools, the description is reasonably complete.
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 already covers all three parameters with descriptions (100% coverage). The description adds only the inclusive range caveat and an example format via the schema. This is marginally beyond the schema but does not substantially enhance understanding of the parameters themselves.
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 tool retrieves historical electricity prices between two ISO 8601 dates, with the inclusive range nuance. It distinguishes from siblings like get_current_price and get_day_ahead_prices by explicitly mentioning 'historical' and gives concrete use cases (backtesting, charts, 'what did power cost last week?').
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 provides clear usage context: backtesting, charts, and historical queries. It also mentions a prerequisite (API plan requirement), which helps the agent determine feasibility. However, it does not explicitly name alternatives or state when not to use this tool, so it falls short of a 5.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.