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

Annotations already indicate readOnlyHint=false and destructiveHint=false. The description adds value by disclosing that credits are spent, a simulation result is recorded, and the simulation is non-deterministic ('random crisis'). This goes beyond annotations, but could still mention state changes more explicitly.

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?

Two sentences: first states the core purpose, second gives essential usage conditions. No fluff, front-loaded with the key action and differentiator. Every word earns its place.

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?

Given low complexity (2 params, output schema present) and helpful annotations, the description covers purpose, side effects, prerequisites, and even references a sibling tool (get_credits_balance). Output structure is handled by the output schema. It is fully adequate for correct invocation.

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% with descriptions for ideaId and language. The description adds semantic context: 'pass an ideaId you own' clarifies ownership requirement not in schema. No additional info on language beyond default. This incremental value justifies a 4 over the baseline 3.

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 states the tool runs a Survival Mode simulation that throws a random crisis, evaluates idea hold-up, and tests founder resilience. It explicitly says it spends credits and records a result, distinguishing it from read-only siblings like get_simulation_status. The verb 'run' and resource 'survival mode' are specific and unambiguous.

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 clear context: you need an ideaId you own and sufficient credits, even directing to get_credits_balance. It says it's not read-only. However, it does not explicitly contrast with sibling run_* tools (e.g., run_arena_duel, run_time_machine) or say when not to use it, so it lacks full discriminative guidance.

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