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

Annotations already declare destructive=true, idempotent=true, readOnly=false; the description adds rich context beyond them: the replay is forced to a terminal 'aborted' state, the call is a no-op if already terminal, and flow_replay_status may lag a few seconds due to non-interruptible in-flight device calls. This is genuinely useful behavioral disclosure.

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 core action and its routing condition, and every sentence carries information (watchdog bounds, no-op semantics, status lag). It is somewhat long, but the detail is load-bearing rather than 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?

For a single-parameter abort tool with no output schema, the description covers the full picture an agent needs: prerequisites (which tools started the replay), failure scenario, alternatives, idempotent no-op behavior, and eventual-consistency caveat on status.

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 100% and the single replayId parameter is fully documented in the schema. The description only indirectly references the id ('started via flow_replay_start'), adding no format or syntax detail beyond the schema, so baseline 3 applies.

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 (abort) and resource (in-flight replay), and explicitly names the sibling tools that create the replay (flow_replay_start, flow_recording_replay). An agent can distinguish this from flow_replay_status and the watchdog behavior 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?

Explicitly states when to use it ('when a replay stops making progress, e.g. after a device/control-connection error'), names the alternative it replaces ('rather than polling flow_replay_status indefinitely'), and clarifies the boundary vs. the automatic watchdogs (90s per-step, 15min overall) — this tool is for cancelling sooner or cancelling unneeded replays.

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