fable_search

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

No annotations are provided, so the description carries the full burden. It discloses that the tool returns ranked threads with ids, turn/token counts, card titles, decisions, and outcomes. It recommends calling fable_thread to read a thread verbatim, implying a read-only operation. No mention of destructive behavior or rate limits, but the description gives sufficient behavioral context for an agent.

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 a single block but front-loaded with the essential phrase 'RECALL EARLIER CONVERSATION.' It uses capitalization to highlight key concepts. Every sentence adds value, though it could be broken into more structured bullets. Overall, it is efficient and not verbose.

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 complexity of 8 parameters, no output schema, and no annotations, the description provides a clear workflow: search and then call fable_thread to read. It explains the return format sufficiently. Some details like pagination or error handling are missing, but for a search tool, the description is fairly complete.

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 only 38% (3 of 8 parameters have schema descriptions). However, the tool description adds meaning for several parameters: it explains the 'operative' parameter as an 'action-verb facet,' 'target' as a 'file/crate/identifier facet,' and 'tag' as a 'taxonomy filter.' It also explains the overall workflow. This compensates for the missing schema descriptions to a large extent.

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 is for recalling earlier conversations. It distinguishes itself from sibling tools by explaining the workflow: search first, then call fable_thread to read a thread verbatim. The phrase 'RECALL EARLIER CONVERSATION' is a specific verb+resource that sets clear expectations.

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 tells when to use the tool: 'whenever you need context that may be outside your window,' after a compaction, in a long session, or to recall past decisions. It also advises to prefer this tool over guessing or using a compaction summary, noting that the summary is lossy. This provides excellent guidance on when and when not to use the tool.

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