mock_discover_variants

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

With no annotations, the description carries the behavioral burden and does so well: it discloses the grouping keys, the default /action field, the 'null' behavior for GETs and bodies without that field, and the live-source dependency. It stops short of explicitly stating that this is a read-only aggregation, though 'Overview' strongly implies it.

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?

Three dense sentences deliver the full picture with no filler. The main grouping result is front-loaded, followed by usage timing, filters, and the live-source caveat, all in compact, scannable prose.

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?

The output schema covers return values, and the description covers main usage, filters, and the live caveat. But it never explains how history source relates to recording_path, and optional parameters like limit and max_groups are only known by their schema titles. Given 9 parameters and a required source enum, this leaves a meaningful gap for correct invocation.

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 0%, so the description must compensate. It explains body_field's default and semantics, names host_contains/path_contains/methods as filters, and notes capture_id's role for live. However, it leaves recording_path, limit, max_groups, and the history source semantics unexplained, so the compensation is only partial.

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 states a concrete behavior: an overview of the whole captured session, with requests grouped by method, host, path, and request-body field, plus counts, sample entry_ids, and response statuses. This is specific enough for an agent to distinguish it from sibling tools that analyze individual entries or signatures.

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 timing ('right after reading a session'), the main filters to apply, and the condition that live requires capture_id. It does not name sibling alternatives or state when not to use it, but the use context is clear and actionable.

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