get_grid_forecast

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

With no annotations provided, the description carries the burden and does well: it declares 'Read-only; does not touch the task queue', which tells the agent this has no side effects on scheduled work. It also discloses the return semantics (g CO2e/kWh plus categorical bands), which is behavioral context beyond a typical read. It omits any note on forecast accuracy degradation or rate limits, keeping it from a 5.

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 tight sentences, front-loaded with what the tool returns before the usage guidance and the safety note. Every clause earns its place; nothing is redundant with the name or title.

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 tool with no output schema, the description usefully explains return values (units and the five-band categorical scale) and the read-only guarantee. Coverage of the parameters is delegated to a complete schema, which is appropriate. Minor gaps (no note on pagination/horizon defaults beyond the schema, no failure modes for unknown region codes) keep it just below 5.

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 100%, so both parameters (region codes, hours 1-72 with default 24) are already fully documented in the schema. The description reinforces intent with 'for a region' and 'hour by hour' but adds no syntax, format, or edge-case detail beyond what the schema supplies, so the baseline 3 applies.

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 ('Return the projected electricity-grid carbon intensity') plus the granularity ('hour by hour') and scoping unit ('for a region'). An agent can distinguish this from siblings like recommend_window or check_queue_status without opening any schema.

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?

Explicitly names the decision context: 'Use this when deciding whether to run an expensive AI task now or defer it.' That is a clear when-to-use signal. It stops short of naming the sibling alternative (recommend_window) or stating when-not to use it, so it is clear context without full routing guidance.

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