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

With annotations readOnlyHint=true, idempotentHint=true, and destructiveHint=false, the safety profile is already disclosed. The description adds scope content ('delivery-year/LDA filters, UCAP metrics, and citations') but does not reveal behavioral traits such as whether the tool returns metadata only or requires an active session. No contradiction with annotations exists.

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 description is a single sentence with 10 words, front-loading the core purpose without extraneous detail. Every word adds value, and the structure is highly efficient for an agent scanning tool lists.

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 zero-parameter, non-destructive describe tool with an output schema, the description covers the key subjects (filters, metrics, citations) adequately. However, it does not mention how this tool relates to query_power_capacity_market_pjm_v1 or how the described elements map to query parameters, which would improve completeness. The output schema offloads return-value documentation, so the lack of output detail is acceptable.

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 tool accepts zero parameters, so the baseline of 4 applies. The description does not need to explain parameter semantics, and the input schema confirms an empty parameter set, making the description sufficient.

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 specifies the verb 'Describe' and the resource 'PJM RPM delivery-year/LDA filters, UCAP metrics, and citations,' which distinguishes it from sibling tools like describe_power_capacity_accreditation_pjm_v1. However, it does not explicitly explain what 'describe' outputs (e.g., schema definitions, option lists), leaving some ambiguity about the tool's exact behavior.

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 no guidance on when to use this tool versus alternatives. It does not reference the corresponding query tool 'query_power_capacity_market_pjm_v1' or any conditions for preferring this describe tool over others. This lack of usage context forces the agent to rely on naming conventions alone.

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