replay_recall

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

Annotations already mark the tool as readOnlyHint=true, and the description confirms it is a read-only operation by describing memory state reconstruction and search. It adds the requirement for a specific tier, which is useful behavioral context beyond 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 extremely concise, front-loading the core concept, then providing a brief explanation, requirements, and parameter list. Every sentence adds value with no redundancy.

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 existence of an output schema (not shown but indicated), the high-level return description 'JSON string with historical search results' is sufficient. The description fully conveys what the tool does, its parameters, and prerequisites, making it complete for agent use.

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 0% schema description coverage, the description fully compensates by explaining each parameter: 'query: Search query', 'at: ISO timestamp to search at', 'limit: Maximum results (default 5)'. This adds essential meaning beyond the raw schema.

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's purpose: 'Time-travel recall — what would search have returned at a past timestamp?' It explains that it reconstructs memory state and runs semantic search at a historical point, distinguishing it from siblings like 'recall' or other replay tools.

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 context for usage ('Powerful for understanding how agent context evolved') and mentions requirements ('Requires Pro tier or Novyx Cloud'). However, it does not explicitly state when not to use it or compare to alternative tools, missing the highest score.

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