history_search

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

With no annotations, the description carries the burden of behavioral disclosure. It usefully reveals that the tool searches across every registered agent and targets older, cross-project history. However, it does not disclose return format, pagination, performance implications, or how results are aggregated beyond the schema's limited parameter notes.

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 two sentences, front-loaded with the core purpose, and contains no filler. Every clause adds value: 'older', 'cross-project', 'every registered agent', and the specific usage triggers.

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?

Despite good purpose and usage guidance, the tool has 7 parameters, no output schema, and no annotations. The description does not cover required parameter semantics, return value shape, or how the search behaves across connectors/projects, leaving significant gaps for an agent to invoke it correctly.

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 29%, so the description must compensate for undocumented parameters. It does not explain the required 'query' parameter, nor the optional 'model', 'source', or 'project' parameters. The description only hints at 'source/topic' in the usage guidance, which is insufficient for the 7-parameter tool.

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 a specific action ('Search') and resource ('older cross-project history across every registered agent'). It distinguishes this from sibling tools by emphasizing 'older' and 'cross-project', which sets it apart from history_get_recent_context and history_get_thread.

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 gives explicit trigger conditions: 'only when the user explicitly asks to search past history, names an older date/source/topic, or recent context is insufficient.' This strongly implies when not to use it and contrasts with recent-context tools, though it does not name the alternative sibling tools explicitly.

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