get_inbound_activity

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

Goes well beyond the annotations: it warns a row proves recording only, 'not OCR accuracy or physical completion'; clarifies that proposals are agent-only and never charge credits, buy postage, open, forward, or discard on their own; notes policy-checking of forward/discard proposals; states image URLs are never issued to agents; and instructs to stop on denial without switching keys/APIs. This is rich behavioral disclosure an agent cannot infer from the structured fields.

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?

Purpose is front-loaded and sentences are dense but largely purposeful, covering scope, semantics, and safety. It is longer than strictly necessary, with some enforcement-style guidance ('never switch keys or mail APIs to bypass it') that borders on policy lecturing rather than tool usage, keeping it from a 5.

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 read-only timeline tool with an output schema (so return values need not be explained), the description fully covers scope, ordering, pagination intent, key-based visibility, and the proposal/policy caveats. Nothing an agent needs to invoke it correctly appears to be 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 description coverage is 100%, so limit/offset/item_id are already fully documented (including pagination semantics). The description adds only marginal value, restating that item_id narrows to one item, with no additional syntax, constraints, or interaction detail. Baseline 3 is appropriate when the schema carries the burden.

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 and resource ('Read the inbound timeline through GET /v1/inbound-activity') and enumerates the returned event types (received, action proposed/requested/started/completed/rejected) and ordering (newest first). This event-timeline scope is clearly distinct from the item-listing and single-item siblings (list_inbound_items, get_inbound_item).

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?

Provides clear context for narrowing ('Optional item_id narrows to one item') and for key scope (member keys read their own live items; agent keys read bound/assigned items). It does not, however, explicitly name an alternative tool or state when-not-to-use this versus a sibling, so it falls short of the 5-level routing guidance.

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