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

Annotations declare readOnlyHint=true and destructiveHint=false, so the description only needs to add behavioral details. It adds ordering ('newest first'), output fields (artifact_document_id, dates, Filing metadata object), and explains document_type and announcement_type semantics. No contradictions with 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?

The description is front-loaded with the main action, followed by usage guidance, then output details. It is somewhat lengthy due to enumerating announcement_type values, but all information is relevant. 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?

No output schema exists, so the description carries the burden of explaining return values. It does so by describing row contents (artifact_document_id, dates, Filing metadata, document_type, announcement_type). It also provides context for registry selection. However, it omits details on limit behavior and how ticker vs company interact, leaving small gaps.

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 only 40% (document_type and filing_registry have descriptions; limit, ticker, company lack schema descriptions). The description clarifies filing_registry usage and expands on document_type and announcement_type values, but does not explain limit, ticker, or company parameter semantics, leaving partial compensation for the low coverage.

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 begins with 'List available filings for a ticker (newest first) with artifact_document_id and dates', clearly specifying the verb (List), resource (filings), and scope (ticker, ordering). It distinguishes from sibling tools like get_latest_filing and get_filing_toc by focusing on listing all filings, not a specific one.

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 provides explicit usage guidance: 'Use filing_registry=fca_nsm for UK FCA NSM reports' and 'Use this first when you need a specific reporting period.' This indicates when to use it, though it does not explicitly state when not to use it or name alternatives.

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