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

Goes beyond the annotations by disclosing that publishing may notify users, that the returned state is authoritative, and that the action cannot be undone through MCP. This is meaningful context on side effects and irreversibility that the destructiveHint/idempotentHint flags alone don't convey, though it doesn't cover auth requirements or rate limits.

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 short sentences, front-loaded with the core action and state transition, then side effects, then the routing pointer. No filler or repetition.

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 an output schema present, return values need not be explained, and the annotations carry the safety profile; the description covers the remaining agent-critical facts (irreversibility, notifications, post prerequisite via schema). Only minor gaps remain, such as permission requirements for publishing.

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% and the single 'id' parameter already documents that it must be a DRAFT stream you own with a post prerequisite. The description's 'owned draft stream' phrasing merely restates the schema, adding no new syntax or format detail, so the 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?

States a specific verb (publish) and resource (an owned draft stream) plus the resulting state change to ACTIVE. This is clearly distinguishable from create_stream, update_stream, and create_stream_post in the sibling list, and the 'owned draft' qualifier scopes it precisely.

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 routes one adjacent need ('Use create_stream_post to add posts') but never states when to publish versus when not to, nor what the caller must have done first (the schema, not the description, carries the 'needs at least one post' prerequisite). Usage is implied rather than spelled out.

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