board_register

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

With zero annotations, the description carries the full burden and does well: it discloses that identity is token-derived and the agent name is not choosable, that the call is a once-per-session operation, and how resume works. It does not describe error behavior, what happens if called twice, or session lifetime, which keeps it from 5.

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 correctly front-loaded, but roughly half the text is a generic board-wide security policy rather than behavior specific to registering a session, which bloats a three-optional-parameter call. The parameter notes are terse and useful; the security block would be better placed as shared context.

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 simple 3-optional-param registration call with no output schema, the description covers the essential mechanics — timing, identity source, path semantics, and resume — and states that a session_id is returned. It leaves out idempotency/re-registration behavior, which an agent might reasonably want to know.

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 coverage is 0% and the schema gives only titles, but the description compensates for all three parameters: 'project = absolute path of the main repo you work in', 'worktree = your git worktree path if different', and the resume semantics of resume_session_id. It could be sharper on the fact that resume_session_id is an integer session_id returned by a prior registration.

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 opening sentence states a specific verb and resource — 'Register this agent session on the board and get a session_id' — with no ambiguity about the outcome. None of the siblings (board_post, board_claim_task, board_release_task, etc.) perform session registration, so it is cleanly distinguishable.

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?

'Call once at session start' gives explicit timing, and 'Pass resume_session_id to continue a session you registered earlier' gives a clear condition for the resume path. It does not name a when-not case or an alternative (there is no sibling that registers sessions), so it stops short of 5.

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