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

Beyond annotations, the description discloses important behavioral constraints: OAuth account requirement, phone verification, 10/day SMS cap, always-on feed behavior, and the fact that webhook signing secret is returned once. These details help the agent anticipate failure modes and side effects, adding significant value beyond readOnly/idempotent hints.

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 dense and front-loaded with the core purpose, followed by prerequisites, types, and delivery details. Every sentence carries useful information, but the length is substantial and could benefit from light formatting (e.g., bulleted types). It is not wasteful, but not as crisp as minimal high-quality examples.

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?

Given the tool's complexity—multiple subscription types, nested params, and optional delivery channels—the description covers requirements, supported types with examples, delivery behavior, and return value. The schema fills in remaining nested-object structure, so the combined definition is complete even without an output schema.

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?

Although schema coverage is 100%, the description substantially expands each parameter's meaning: sec_8k item codes (e.g., items:["5.02"] = officer change), polymarket_edge topic, fred_series series_id, and delivery channel semantics including webhook HMAC signing. This is far beyond baseline and helps the agent set correct values.

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 opens with a specific verb and resource: 'Create a proactive monitoring subscription to a live-data event stream. Returns the new subscription id.' This clearly distinguishes the tool from siblings like list_subscriptions, unsubscribe, and recent_alerts, and states the key output.

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?

The description gives clear context for appropriate use: requires a Pipeworx OAuth account, notes that anonymous/BYO cannot persist subscriptions, and lists supported types with examples. It also mentions that the feed is always on and can be pulled via recent_alerts or the registry URL, hinting at alternatives for reading alerts. It stops short of explicitly naming alternative tools for every scenario, so 4 rather than 5.

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