ddflow_history

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

With no annotations, the description carries the full behavioral burden. It discloses that results are ordered chronologically and adds a valuable operational detail: exit 2 means nothing matched and should be treated as an answer, not a failure. It does not explicitly state permissions or read-only behavior, but that risk is low for a history view.

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?

Two dense paragraphs with no wasted repetition. The first front-loads the core purpose and selection context; the second delivers filter semantics and the non-obvious exit-code meaning. Every sentence contributes to correct selection or invocation.

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 history-listing tool with no output schema, the description covers purpose, ordering, filtering, and a non-obvious exit-code behavior. It does not specify the exact return shape, but 'ONE timeline' plus the event-family list is enough for an agent to invoke and interpret it. The main gap is not naming specific sibling alternatives.

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?

The input schema already covers all four parameters, so the baseline is 3. The description adds conceptual meaning: `item` means one task's whole life, `kind` groups event families, and `since` defines a time window. It does not add much about `limit`, but the schema already documents that.

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 defines a single timeline of events in chronological order and enumerates the event families it covers. It contrasts itself with 'the other views' that answer current state, which helps an agent distinguish it from status-like siblings, though it never names a specific alternative tool.

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 explicit context for when to use the tool: when something looks wrong and the question is 'how did it get like this.' It also explains filter usage and exit code 2 as a valid no-match result. However, it does not name specific sibling tools or state when not to use it, so it stops 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.