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

With readOnlyHint already covering the safety profile, the description still adds rich context: csv mode returns a 24h signed download_url of the FULL import with no filters or annotations, mapping is the only routing path (no fuzzy match), __ignore__ rules yield 'ignored', and legacy materialized imports derive one row per owned cell. These are behavior traits annotations cannot express.

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?

Front-loads what is returned, then layers in filtering, the csv variant, and the legacy edge case. It is a dense single paragraph where each clause carries information, though the wall-of-text density slightly hurts scanability.

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?

With no output schema, the description carries the full burden and does so: it describes annotated rows, the routing labels (rule/auto/skip reason/ignored), the csv download_url shape, and the legacy-import row derivation. An agent has enough to call and interpret 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 coverage is 100% (baseline 3), but the description adds meaning beyond the schema: period is YYYY-MM, q matches description/category substrings, and csv format deliberately ignores filters while json annotates inline. The interplay between format and the other filters is not obvious from the schema alone.

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?

Opens with a specific verb+resource: returns a data source's staged transactions, then immediately scopes them as 'annotated with their routing'. It distinguishes itself from siblings like layerz_list_mappings and layerz_list_integrations by clarifying that this lists the staged rows themselves, not the mapping definitions.

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?

Explains how period and q filter rows and when format:'csv' applies (full import, no filters, no annotations), which routes the agent between the two modes. It does not explicitly name an alternative tool or state when-not-to-use, 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.