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

Beyond the annotations (which cover mutation, idempotency, and safety), the description adds meaningful behavioral context: provisional rather than canon status, separation of established progress from unresolved ideas, a restriction against sending transcripts/credentials/personal details, and retry guidance. These additions are substantial and consistent 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 front-loaded with the core purpose, then adds constraints and retry behavior in tightly packed sentences. Every sentence serves a distinct function—purpose, scope limitation, content partitioning, safety restriction, and idempotency—with no filler.

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 the rich annotations and the presence of an output schema, the description covers purpose, usage conditions, content restrictions, and retry semantics well. The main gap is parameter-level detail for a 6-parameter tool with zero schema description coverage, though the parameter names are mostly self-explanatory enough for an agent to proceed.

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% and there are 6 parameters, so the description carries the full burden. It explicitly mentions checkpointId ('Reuse checkpointId on retries') and gives content guidance that loosely maps to storyState and openThreads, but it never explains title, projectId, nextSteps, or the required format/length constraints, leaving most parameter semantics undocumented.

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 states a specific verb ('Preserve', 'Stores') and resource ('story-session handoff', 'provisional notes'), and explicitly distinguishes what it is not ('not canon or an approved scene'). This differentiates it from siblings like upsert_canon_entry and record_approved_scene without needing to open 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?

It gives clear conditions for use ('when the user asks to save progress or has authorized ongoing checkpoints') and implicit exclusions ('not canon or an approved scene'). However, it does not explicitly name alternative tools or state when to use a sibling instead, which keeps it short of a 5.

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