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

Annotations already declare readOnly/idempotent/non-destructive/closed-world, so the safety profile is covered. The description adds real behavioral context the annotations cannot: a hard budget of at most five provider operations, an explicit precondition (expiration for skew/activity) that the enum schema does not enforce, and a data-quality caveat that coverage is bounded and never whole-chain totals. It stops short of describing pagination or the shape of the response.

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?

Four short sentences, each carrying distinct information (prerequisite, outputs, quota, conditional requirement, caveat), with nothing padded. The telegraphic style — fragmented noun phrases like 'Expected move, near-money skew/activity or IV history' — trades a little readability for density.

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 8-parameter, no-output-schema tool in a specialized domain, the description covers purpose, prerequisites, operation budget, and coverage limits well. It is incomplete on how history_days and strike_count shape results and on whether limit/offset/path imply a paged field-directory response, which an agent would need before invoking it reliably.

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 13%, so the description must carry weight. It does explain the central 'question' enum values and the conditional expiration requirement, but leaves history_days, strike_count, path, limit, and offset undefined; limit/offset/path are plausibly generic pagination, yet the domain-specific numeric parameters remain unexplained in both schema and description.

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 the concrete outputs (expected move, near-money skew/activity, IV history) and the scope (one equity or futures root), which is enough to distinguish it from bulk siblings like read_options_history. It is delivered as a noun phrase rather than an explicit verb, so the 'what it does' is inferred rather than stated, keeping it just short of a 5.

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 gives useful preconditions — a SignalDock account connection is required, and skew/activity require an expiration — but it never says when to pick this over read_options_history, compare_symbols, or research_company. Usage is implied by the listed question types rather than contrasted against alternatives.

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