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

Annotations already declare readOnlyHint=false, destructiveHint=false, and openWorldHint=false; the description's "fictional" and "synthetic" wording usefully explains why a write is non-destructive. It says nothing about idempotency, whether an existing outcome for the same action_id is replaced or rejected, or what permissions the sandbox_key requires.

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?

A single front-loaded sentence with no filler, which is structurally clean. Its brevity borders on under-specification given the parameter load, but nothing in the text is wasted.

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 an 8-parameter write tool with no output schema and zero schema descriptions, one sentence is not enough to call it correctly. Key omissions are the relationship between evidence_kind, evidence_ref, and baseline_value, and the record-vs-verify distinction from its sibling.

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 0% across 8 parameters, including 5 required ones, so the description carries the full burden and does not meet it. "Typed synthetic evidence" lightly gestures at evidence_kind/evidence_ref but never explains the default "self_report", what evidence kinds exist, metric_unit format, or the role of baseline_value.

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 ("Create") and resource ("reported fictional outcome") and adds the qualifier that evidence is typed and synthetic, which is informative. It does not distinguish this from the obviously related sibling reserve_sandbox_verify_outcome, so an agent cannot tell from the text why it should record an outcome rather than verify one.

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?

"Reported fictional outcome" implies sandbox/self-reported usage context, which is mild implied guidance. There is no explicit when-to-use, no prerequisites, and no naming of alternatives such as verify_outcome or record_action, so the agent must infer the routing decision.

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