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

With no annotations, the description carries the full burden and does substantial work: it discloses the response composition, the recency-bias mitigation side effect of agent_id, the vocabulary_signal triggered by question, and the diff triggered by last_visited. It stops short of stating permissions or whether the call itself mutates state (focus is recorded as presence), leaving a minor gap for a no-annotation tool.

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?

Front-loaded with the key classification ('PRIMARY ENTRY POINT'), then structured into purpose, replacement list, and per-parameter guidance. It is dense and long, but each sentence conveys distinct actionable information rather than padding.

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?

No output schema exists, so the description must describe returns, and it does so thoroughly by enumerating every section of the response. Combined with complete parameter coverage, an agent has everything needed to call and interpret this tool correctly.

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 already 100%, so baseline is 3, but the description adds genuine meaning beyond the schema: agent_id enables automatic recency-bias mitigation downstream, question triggers a vocabulary check plus tailored first move, and last_visited yields a change diff. Only focus is left to the schema alone.

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/resource ('orients you to the graph') and enumerates the exact contents returned (shape stats, live tensions, hot pieces, messages, deposits, suggested_first_move). It explicitly names the sibling tools it replaces (graph_stats + active_frontier + read_messages + graph_changes_since), so an agent can distinguish it without opening a 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?

Declares itself the 'PRIMARY ENTRY POINT for new sessions' and gives per-parameter routing rules: pass agent_id always, pass question if you arrived with one, pass last_visited if you want a diff. The alternatives it supersedes are named explicitly, leaving nothing to inference.

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