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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so the safety profile is covered. The description adds substantive context beyond that: authentication is required, entitlement is enforced upstream by OilPriceAPI (so auth failures surface as provider-side errors), and missing expiration/source dates are silently unreported rather than flagged.

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?

Four short sentences with the core scope front-loaded and no filler. The 'Preserve ... semantics' and 'Missing ... remain unreported' sentences are dense but each carries real information, though their phrasing is terse enough to be slightly ambiguous.

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?

With no output schema, the description sensibly sketches returned dimensions (contract month, trading date, expiration) and warns that some dates may be absent, which is genuinely useful. It falls short on selection guidance versus siblings and on documenting the instrument enum, both of which an agent needs to call this correctly.

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% with two required parameters, so the description must carry the burden. It restates the limit cap (already expressed as maximum=12 in the schema) but says nothing about the instrument parameter or its six-value enum (brent, wti, natural-gas, gasoil, ttf-gas, lng-jkm), leaving the most consequential choice undocumented. The phrase 'Preserve contract month, trading date and expiration semantics' hints at output fields rather than clarifying inputs.

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 verb and resource ('Read an authenticated energy forward curve') plus a hard scope cap ('at most 12 contracts'), which tells an agent this is a single-curve read rather than a history or comparison call. It never names a sibling (energy_get_latest, energy_history, energy_compare) to draw the boundary, so the differentiation is only implied.

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 guidance: nothing says when a forward curve is preferred over energy_history, energy_get_latest, or energy_compare, and no prerequisites or exclusions are stated. The agent must infer routing from the tool name alone.

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