Open Play Session

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

Annotations already declare destructiveHint=true, readOnlyHint=false and idempotentHint=false, and the description adds real context beyond that: changes persist, are audited, and both parameters silently fall back to active defaults. It does not explain what the destructive behavior actually overwrites (e.g., whether an existing badge or session state is clobbered), which is the one thing an agent calling a destructive tool most needs.

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?

Front-loaded with the action, then defaults, then use/don't-use routing and the revert path – every clause carries information. Slightly dense in places (the long compound first sentence, jargon like 'badge the seat'), but no wasted sentences.

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?

Strong coverage for a mutation tool: output schema handles the recap return value and annotations carry the safety profile, so the description only needs routing and default behavior, which it supplies. The remaining gap is the unexplained destructive consequence, which would matter more if annotations were 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?

With 100% schema coverage the baseline is 3, and the description earns a step up by explaining that both parameters are optional and default to the active Novel and current badge. That fallback semantics is behavior the schema's per-field descriptions do not convey.

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?

States a specific verb and resource with its composite effects: opening a session by resuming a Novel, activating a badge, and returning a recap. This is clearly distinguishable from siblings like take_turn, manage_novel, and close_session without opening any schema.

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?

Explicit 'Use when' (starting/resuming a session, especially after a restart) and 'Do NOT use when' clauses route to named alternatives: manage_novel (action: create) for creating, take_turn for running a turn, and manage_history (action: undo) as the revert path. Nothing 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.