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

Since all annotations are false (not read-only, not idempotent, not destructive), the description carries the full burden of behavioral disclosure—and it succeeds. It reveals that omitting traffic causes a random 2×–5× spike, that RPS is capped at 10000, that changes only affect metrics after simulation.step, and that the tool can return NO_ACTIVE_SIMULATION without a valid session. There is no contradiction with the annotations.

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 long but front-loaded with the core operation and every clause carries decision-relevant information. It is slightly dense, especially the final session/security caveats, which could benefit from bulletizing, but overall it is efficiently structured and appropriately sized for the tool's complexity.

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 state-changing tool with an output schema, no required parameters, and false annotations, the description covers invocation variants, side effects, error cases, and the likely next step. An agent has everything it needs to select and call the tool correctly without consulting external documentation.

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; however, the description adds substantial meaning beyond the schema. It explains when to omit traffic, the internal random flag, when to pass simulationId for fresh sessions, the current-simulation default, the NO_ACTIVE_SIMULATION error, and why the ID is not a durable share link. This far exceeds the schema's own descriptions.

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 opens with a specific verb-resource pair ('Change the traffic load') and immediately states the tool's demo-simulation context. It then explicitly says what not to use it for, naming simulation.metrics and simulation.step, which clearly differentiates it from its siblings.

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?

It gives explicit when-to-use guidance ('use it to stress-test the architecture before stepping') and names the alternative tools for reading metrics and advancing time. It also tells the agent what to do next (simulation.step) and how to handle the session-sensitive simulationId, leaving no ambiguity about correct invocation.

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