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Glama

storage_container_update

Destructive

Resize a storage container's capacity or replication factor in Nutanix Prism Central. Omit fields to leave values unchanged; changes are reversible.

Instructions

[WRITE][risk=medium] Resize a container's capacity / replication (reversible → prior).

Args:
    ext_id: Storage container extId as returned by storage_container_list.
    max_capacity_bytes: New max capacity in bytes (omit to leave unchanged).
    replication_factor: New replication factor (omit to leave unchanged).
    target: Prism Central target name from config; omit for the default.

Input Schema

NameRequiredDescriptionDefault
ext_idYes
targetNo
max_capacity_bytesNo
replication_factorNo

Schema Changelog

Changes observed during successful MCP inspections.

  1. First observedv0.1.0

TDQS

A4.2/5.0
Behavior4/5

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

Annotations already declare readOnlyHint=false, idempotentHint=false and destructiveHint=true; the description adds the risk grade (medium), states the change is reversible to the prior state, and notes that omitting capacity/replication leaves them unchanged. It does not mention that non-idempotent behavior means repeated calls are not safe to assume, but the added context is substantive.

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

Conciseness4/5

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

Front-loaded with the operation class and risk tag, then a one-line purpose, then a tight arg list; nothing is padded. The '(reversible -> prior)' shorthand is slightly cryptic, which keeps it out of 5 territory.

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

Completeness4/5

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

For a mutation tool with no output schema, the definition covers parameters, risk, reversibility, and required identifier well. It omits failure modes, permission requirements, and any post-change verification step, but nothing essential for correct invocation is missing.

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

Parameters5/5

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

Schema description coverage is 0%, yet the description documents all four parameters: ext_id with its provenance (storage_container_list), max_capacity_bytes and replication_factor with units and the 'omit to leave unchanged' semantics, and target with its config-prefix and default behavior. This compensates fully for the bare schema.

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?

States a specific verb and resource ('Resize a container's capacity / replication') and scopes exactly which attributes change. It is immediately distinguishable from sibling storage_container_create, storage_container_delete, and storage_container_list.

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

Usage Guidelines3/5

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

The [WRITE][risk=medium] tag and the '(reversible -> prior)' note tell the agent this is a mutating, undoable operation, which implies usage context. However, it never says when to use this versus storage_container_create/delete or when resizing is inappropriate, so guidance is only implied.

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