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

With no annotations, the description carries the burden of behavioral disclosure. It discloses the screening nature, the outputs reported, the cost after five trial uses, and directs to docs/example. It does not mention whether comparisons are saved or recoverable, which the sibling recover_solar_battery_comparison hints at, so the disclosure is good but not exhaustive.

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 sentences with the main purpose front-loaded and no filler. The cost and docs references are useful, though the middle sentence packs output details and caveats densely rather than using structured formatting.

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?

The tool has 13 required parameters, no output schema, and no annotations, so the description needs to carry a heavy load. It provides an overview, cost model, output areas, and docs links, but it does not describe the input format, array constraints, enum meanings, or return structure sufficiently for an agent to invoke it correctly without external documentation.

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 0%, so the description must compensate for 13 undocumented required parameters. It loosely groups inputs into 'monthly kWh, hourly shapes, fixed rates and costs,' but does not explain key parameters such as input_basis, inputs_as_of, model_version, battery_options fields, or the meaning of hourly weight arrays. This leaves significant semantic gaps.

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?

Description states a specific verb and resource: compare solar alone against up to three battery sizes for a GB household. It also distinguishes this from the sibling retrieval/lookup tools by indicating this is an analytical comparison tool, with a clear caveat that it is a screening estimate, not a forecast.

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?

Usage context is implied: the tool is for comparing solar/battery configurations using monthly kWh, hourly shapes, and cost inputs. It does not explicitly name alternatives or state when not to use it, though 'not a forecast' provides a partial exclusion. No sibling routing is provided.

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