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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, open-world), so the bar is lower. The description adds real behavioral context beyond them: it processes filings chronologically, compares each against the prior filing of the same form, returns only topic-relevant added/removed evidence, and describes the checkpoint persistence pattern the caller must maintain.

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?

Three tight sentences with zero filler; the scope constraint and the checkpoint mechanic are front-loaded, and each sentence adds distinct information (scope, processing model, return + workflow).

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 a 9-parameter, output-schema-less read tool, the description covers scope, processing semantics, return content, and the checkpoint lifecycle an agent must persist. It leaves unspecified the exact shape of the returned records and the non-updated params, but nothing essential to calling it correctly is 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 78% with 9 parameters, so the schema already documents most fields (forms default, limit, maxNewFilings, topic, identifier). The description only sharpens the meaning of sinceAccession via the checkpoint workflow; it adds nothing for history, comparisonLimit, or item, so a baseline 3 is appropriate.

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 ('check') and resource ('one issuer for new monitored filings'), plus the incremental scope ('since an optional checkpoint accession'). The incremental-checkpoint framing distinguishes it conceptually from a full-scan sibling, but the description never names scan_disclosure_changes or compare_filings, so the differentiation is left to inference.

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?

Gives clear operational context for the first call ('Omit for the first snapshot') versus subsequent calls ('Save checkpoint.accession and supply it on the next call'), which is genuine when-to-use guidance for a stateful tool. However, it offers no exclusions or comparison against the closely-named scan_disclosure_changes alternative, leaving the boundary with siblings ambiguous.

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