get_delegation

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

Annotations only declare readOnlyHint, but the description goes well beyond that: it discloses that the response carries a stored publishable token plus DERIVED effective_status/is_valid, and explains the derivation rule (a revoked/suspended/expired control proof invalidates it; expires_at caps it independently). That derivation logic and the auth prerequisite are exactly the behavioral context structured fields cannot convey.

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-loads purpose, then the derived-status semantics, and ends with access prerequisites — a sensible ordering with no filler. The ACCESS sentence ('Set PROOF_API_KEY and restart this server, then call this tool again') is a touch verbose but operationally useful, so it earns its place.

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 carries the return-value burden and does so by naming the token and derived status fields. Combined with the explicit auth/access prerequisites, an agent has everything needed to call this 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 description coverage is 100% for the single id parameter, including the regex pattern, so the schema already carries the semantics. The description's 'Mongo id or ph_dlg_* handle' merely restates the accepted formats, adding no syntax detail beyond it — baseline 3.

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 ('Get one of your delegations') and the two accepted identifier forms (Mongo id or ph_dlg_* handle). The singular 'one of your delegations' cleanly separates it from list_delegations without needing to name it, so the agent can route correctly.

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?

Gives clear usage context via the ACCESS block: a Proof account is required, PROOF_API_KEY must be set, and notably start_login does NOT unlock this tool, which is a real exclusion that saves the agent a dead end. It stops short of routing to named alternatives (e.g. list_delegations vs verify_delegation), so it is not a full 5.

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