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

No annotations exist, so the description carries the full load and does well: it discloses the keyset-delta semantics, that cursors are stable across restarts, what the response contains (changed_count and a new next_cursor), and the $0.01 x402 cost. It does not spell out auth mechanics beyond the x402 price line or rate limits, which keeps it short of a 5.

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?

Dense but front-loaded: the core delta behavior and cursor usage lead, with the HTTP/price/docs bracket trailing as reference metadata. Most sentences earn their place, though the endpoint/pricing bracket is somewhat boilerplate.

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?

With no output schema, the description steps in to describe the return shape (changed_count plus a new next_cursor) and the bootstrap flow. For a two-parameter paid delta endpoint this is essentially complete; only auth/rate-limit detail is absent.

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 only 50% (the 'form' enum is undocumented), but the description compensates for the important parameter by explaining the cursor's provenance and lifecycle: where 'since' comes from, that it is opaque, and that omitting it bootstraps at now. It reinforces rather than merely repeats the schema text for 'since'.

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 names a specific verb+resource ('delta of /v1/edgar/watch/:form') and precisely scopes it: only filings of the watched form added or changed after the cursor. It distinguishes itself from the sibling gov_edgar-watch_changes by casting that one as the free count-only endpoint, so an agent can route without opening 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?

Explicit operational guidance: pass since=<next_cursor from your last call>, omit it once to bootstrap, and poll the free sibling for counts and only pay when there is something to fetch. This is exactly when-to-use plus a named cheaper alternative.

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