router_read_sms

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

No annotations are provided, so the description carries the full burden. It does disclose one genuinely useful behavioral fact — that a "Network Guard safety check" exists and force bypasses it — but it never explains what that guard blocks, what happens if force is omitted, or whether reads have side effects on the inbox.

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 purpose is front-loaded in a single sentence, followed by a compact Args block. The Args entries mostly restate the schema types, but the whole thing is short enough that no sentence is a real liability.

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?

An output schema exists, so return values need no explanation, and all three optional parameters are documented. The only gap is the semantics of the Network Guard check that force interacts with, which leaves the agent guessing about the default safety posture.

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 0%, so the description must compensate, and it largely does: all three parameters are explained, including the allowed folder values ('inbox' or 'sent') which appear nowhere in the schema and would otherwise be free-form strings. Only the force parameter's consequences remain underspecified.

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 ("Reads incoming or sent SMS messages from the router SIM inbox") and scopes it to the SIM-stored messages rather than device notifications. This cleanly separates it from the sibling router_send_sms, which is the only other SMS tool in the list.

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 parenthetical "e.g. package expiry alerts" hints at a use case, and the force parameter implies there is a guard to work around, but there is no explicit statement of when to prefer this tool, no prerequisites, and no exclusions. Usage must be inferred from the name and context.

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