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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is fully covered. The description's contribution beyond that is listing the state fields returned, which largely duplicates the output schema. It adds nothing about behavior an agent might need, such as what happens with an unknown or stale runtime_id.

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?

One sentence, front-loaded with the verb and scope, then the returned state fields. Every clause carries information and there is no filler or repetition.

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 an output schema present, the description does not need to enumerate return values, and the one required parameter is fully documented in the schema. The tool is a simple idempotent read, so the definition is essentially complete; only a note on invalid or missing runtime_id behavior 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?

There is a single parameter with 100% schema description coverage, and the schema already explains where the id comes from (spotgrid.list_runtimes) and how to identify the primary grid. The description adds no further meaning about runtime_id. Baseline 3 is correct when the schema does the work.

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 names a specific verb and resource ("Reads one runtime's current state") and enumerates exactly what that state comprises: running/stopped, paper/live mode, network, kill-switch, open order counts, latest ticker. This implicitly separates it from spotgrid.get_config (static configuration) and spotgrid.get_assurance_status. It stops short of naming a sibling explicitly, so it is clear but not maximally differentiated.

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 is only implied: an agent can infer this is the tool for a point-in-time runtime health/state check. There is no statement of when to prefer this over spotgrid.get_config or spotgrid.get_assurance_status, and no exclusions. Adequate for a self-evidently named read tool, but the sibling boundary is left to inference.

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