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

Annotations already carry the safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false, openWorldHint=true). The description adds only that output is CSV, but says nothing about whether this is synchronous, whether large exports are paginated/async, whether the CSV is returned inline or via a download URL, or any rate limits — leaving real behavioral gaps despite the lower bar set by annotations.

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?

A single sentence, front-loaded with the core action and output format, with the optional-field behavior trailing. Nothing redundant and no filler.

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 export tool with nested body params and no output schema, the description covers the essentials (what is exported, output format, optional column groups). It is slightly thin on how the CSV result is delivered and how the signal-template columns are named/derived, but the schema already explains the column rules, so the remaining gap is minor.

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 100%, so both parameters (listId, fields, signalTemplateIds) are already fully documented in the schema, including the 422 behavior and the two-columns-per-subscription rule. The description only loosely maps 'firmographic and enrichment columns' onto the two optional arrays, adding little beyond what the schema states, so the baseline 3 applies.

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 specific verb (Export), resource (a saved company list), and output artifact (CSV), which cleanly distinguishes it from siblings like company_lists-get_companies (returns companies) and company_lists-count_preview (returns counts). An agent can identify this as the CSV-generation tool without opening any 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?

Usage is only implied: the mention of 'saved company list' and 'CSV' signals it is for extracting a list to a file, but there is no explicit when-to-use guidance, no mention of prerequisites (e.g., the list must exist), and no comparison against alternatives such as company_lists-get_companies.

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