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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds real value by disclosing data provenance — the modelled path is indicative while inputs and the anchor are published data — which tells the agent how much to trust the numbers. It says nothing about payload size (up to 60 monthly rows) or how the model run is performed.

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 output enumeration is front-loaded and the provenance caveat is a valuable closing line, but the opening sentence is an overlong stack of clauses that takes effort to parse. The scenario sentence reads like a schema artefact pasted into prose rather than a well-integrated explanation.

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, two-optional-parameter tool with no output schema, the description does the needed work of describing the return shape and its reliability. Minor gaps remain around the scale of the monthly path and whether the run is deterministic, but nothing an agent needs in order to invoke it correctly is absent.

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 coverage is 100%, so the baseline is 3, but the description goes further by explaining what each scenario value means (tight = stronger demand against tighter supply, transition = weaker demand with more displacement, flood = more supply and more elastic shale). That semantic gloss on the enum is not in the schema. Horizon is left to the schema's documented default of 36 months.

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 a specific resource (the platform's oil balance model) and spells out exactly what comes back: lever set, summary, and a monthly path of anchor, price, band, demand, supply, stock change and inventories. It does not name or distinguish itself from siblings such as oil_outlook or oil_scenario, so an agent cannot route between them from this text alone.

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?

There is no when-to-use or when-not-to-use guidance and no reference to the neighbouring outlook/scenario tools. The only usage-adjacent content is the enumeration of scenarios, which is parameter meaning rather than tool selection guidance.

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