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

With no annotations, the description carries full behavioral burden and does so: it discloses the exact ordered pipeline (explode, flatten, trim, lower emails, phone normalization, URL host/slash handling, type coercion, empty-to-null, column ops, dedup), the default dedup normalization and 'most complete row' survival rule, determinism, and the per-call row limit.

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?

Purpose and return shape are front-loaded, followed by the pipeline then usage notes, so an agent can stop reading early. It is dense rather than padded, though the long middle sentence enumerating every transform is heavier than strictly necessary.

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 an 18-parameter, annotation-free tool with no output schema, the description covers the gaps: it describes the returned summary fields and counts, the warning behavior, determinism, and the size constraint. Nothing required to invoke it correctly is obviously missing.

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 already 100%, so the baseline is 3, but the description adds real semantics beyond the schema: the order in which steps run, that dedup compares the whole row unless dedupKeys is set and that key names must be final flattened/renamed names, and how blank-vs-null and type coercion interact.

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 opens with a specific set of verbs and resource ('Deduplicates, flattens and cleans a list of JSON rows') and states the return shape (spreadsheet-ready rows/CSV plus a summary). This is unmistakably distinct from the only sibling, list_capabilities, without needing to open either schema.

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 concrete usage context ('scraped leads, CRM exports or API results before loading them anywhere') and points at list_capabilities for the row limit, plus the workaround of splitting large lists across calls. It lacks an explicit 'when not to use' or an alternative-tool comparison, 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.