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renew

Idempotent

Prevent lease expiry during long-running tasks by extending every held lease for its original TTL and restarting the four-TTL age limit.

Instructions

Extend every lease you hold by its original TTL and restart the four-TTL age limit that ends a lease however active you are. Needed only during long work with no other call, because any tool call already renews; to take new paths use claim. Returns how many leases were renewed and the latest expiry; not_found when you hold none.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`agent`	Yes	Your stable agent name.

Output Schema

TableJSON Schema

Name	Required	Description
`agent`	No	The caller.
`count`	No	Leases renewed.
`status`	Yes	ok. not_found: you hold no claims. invalid: bad input.
`message`	No	Human-readable detail, on most outcomes other than ok.
`expires_at`	No	RFC 3339 latest expiry among the renewed leases.

Schema Changelog

Changes observed during successful MCP inspections.

Changed2 schema fields changedv1.1.2Sep 18, 2026

addedInput schema / properties / agent / description
```
Added value: +"Your stable agent name."
```

changedOutput schema / (root)

Previous value: -nullNew value: +{
+  "description": "Any result may also carry lost, inbox, inbox_more and persist_error; see guide.",
+  "properties": {
+    "agent": {
+      "description": "The caller.",
+      "type": "string"
+    },
+    "count": {
+      "description": "Leases renewed.",
+      "type": "integer"
+    },
+    "expires_at": {
+      "description": "RFC 3339 latest expiry among the renewed leases.",
+      "type": [
+        "string",
+        "null"
+      ]
+    },
+    "message": {
+      "description": "Human-readable detail, on most outcomes other than ok.",
+      "type": "string"
+    },
+    "status": {
+      "description": "ok. not_found: you hold no claims. invalid: bad input.",
+      "enum": [
+        "ok",
+        "conflict",
+        "not_found",
+        "none",
+        "invalid",
+        "cancelled"
+      ],
+      "type": "string"
+    }
+  },
+  "required": [
+    "status"
+  ],
+  "type": "object"
+}

First observedv1.1.1Sep 18, 2026

TDQS

A4.7/5.0

Behavior5/5

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

Annotations already declare idempotentHint=true and destructiveHint=false, and the description adds meaningful behavioral detail: the TTL extension mechanism, the four-TTL age-limit restart, the 'not_found' outcome, and the fact that any tool call renews. No contradiction with annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Three tight sentences each earn their place: first states the core behavior, second gives usage guidance, third covers return values. No fluff, and the most important information is front-loaded.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a one-parameter tool with an output schema and safety annotations, the description fully covers behavior, usage conditions, alternatives, return values, and error cases. Nothing an agent needs to invoke it correctly is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100% and the single agent parameter is fully documented in the schema. The description does not add parameter-level detail, which is acceptable because the schema already carries that burden.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description states a specific action (extend leases by original TTL) and resource (all held leases), and explicitly contrasts with claim for taking new paths. It clearly differentiates renew from its siblings.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description gives an explicit when-to-use condition ('Needed only during long work with no other call'), explains why (any tool call already renews), and names the alternative for different situations ('to take new paths use claim').

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