channel_recv

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

Goes well beyond the readOnlyHint/idempotentHint annotations: it discloses blocking semantics with a 300s default, the trust boundary that 'from' and 'body' are unverified sender-written data, that 'origin' is harness-recorded, and an explicit prompt-injection caution. The blocking behavior is also consistent with idempotentHint=false.

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?

Three tight sentences, with the core read semantics front-loaded before the blocking detail and the safety note. The only minor waste is restating the 300s default that already appears in the schema.

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 usefully names the fields a returned message carries (id, from, body, origin) and explains the blocking/timeout tradeoff. It stops short of describing message ordering, empty-result behavior, or how limit interacts with wait, which an agent might still need.

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 the schema already documents all five parameters including wait, limit, since_id, and timeout_seconds. The description reinforces the wait/timeout behavior and exclusivity of since_id but adds little syntax or meaning the schema does not already carry; baseline 3 applies.

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?

Opens with a specific verb and resource plus a precise scope ('read messages from a named channel after a given message id (exclusive)'). It also frames itself as 'the receiving side of a front/server session coordination flow,' which distinguishes it from the channel_send sibling without requiring the agent to open 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?

Clearly states the condition that selects the blocking mode ('With wait=true, blocks until a new message arrives or the timeout') and gives the default. It implies the polling-vs-blocking choice and its counterpart sender, but never names channel_send explicitly or states when not to use this tool.

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