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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds genuinely useful context beyond that: results are de-duplicated by CIK, the returned fields (entity name, CIK, form type, filing date), and the source API with no key requirement. It omits pagination/rate-limit behavior but the annotations lower the bar.

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-loaded with purpose, then primary use, then a compact example block — every section earns its place. The vertical whitespace is cosmetic and the example list, while longer than strictly necessary, supplies directly actionable query patterns.

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?

An output schema exists so return values needn't be spelled out (they are described anyway), and the read-only annotations cover the mutation profile. Combined with the workflow guidance, an agent has essentially everything needed to call it correctly; only the unexplained inherited boilerplate parameters remain unaddressed.

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?

The schema carries rich per-field descriptions, but the reported coverage of 0% at the params wrapper means the description must help, and it does: four worked examples show concrete keyword/fund_type combinations and the description notes date filtering and de-duplication semantics. It adds real usage value over the raw schema, though it does not address the boilerplate-looking fields (wholesaler_ids, mcp_prompt_id, source_resource_id).

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?

States a specific verb+resource (search SEC EDGAR for mutual fund and ETF filers) and even names the exact form types queried (N-1A, 485BPOS, N-2), which cleanly separates it from siblings like SearchEdgar13F and GetEdgarCompanyFilings. An agent can identify the tool's function without opening the 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?

Explicitly frames the tool as 'Step 1 of fee comparison' and instructs feeding returned CIKs into GetFundFees, which is strong forward-routing. It lacks an explicit when-not-to-use statement (e.g., use GetEdgarCompanyFilings for non-fund entities), so it stops just short of the top score.

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