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Glama

cap_token_check

Verify a short-lived capability token for a specific action, with an optional card, before spend, send, read, or write. Fails closed if invalid.

Instructions

Verify a short-lived cap_token for an action (optional card). Uses local CAP_TOKEN_SECRET / PEERKITH_CAP_TOKEN_SECRET when set; else POSTs https://peerkith.com/cap-token-check. Fail closed.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
cardNo
tokenYes
actionYes

Schema Changelog

Changes observed during successful MCP inspections.

  1. First observedv0.5.1

TDQS

A3.6/5.0
Behavior4/5

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

With no annotations, the description carries the full behavioral burden and does well: it discloses that the token is short-lived, that verification uses local secret env vars when available and otherwise POSTs to a remote endpoint, and that the behavior is 'Fail closed.' This is meaningful beyond the schema. It still omits return semantics and error specifics, so it falls short of 5.

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?

Two compact sentences front-load the core purpose, then add fallback behavior and failure mode with no wasted words. The structure is efficient and appropriately sized for the tool.

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 three-parameter verification tool with no annotations and no output schema, the description is largely complete: it establishes purpose, required inputs, optional input, secret resolution, remote fallback, and fail-closed behavior. Remaining gaps around return values and exact error behavior are minor given the absence of an output schema.

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 description coverage is 0%, so the description must compensate. It identifies all three parameters (token, action, optional card) and adds that the token is short-lived and the card is optional. But it does not clarify what 'card' represents, expected token format, or how action values affect behavior, leaving gaps beyond the enum already present in the schema.

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

Purpose4/5

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

The description states a specific verb and resource: verify a short-lived cap_token for an action. This is clear enough for an agent to understand the operation. However, it does not distinguish itself from similar sibling tools such as cap_check, cap_preflight, or verify, so it stops short of a 5.

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

Usage Guidelines2/5

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

The description gives no when-to-use or when-not-to-use guidance, and it names no alternatives among the closely related sibling tools. Usage is only implied by the verb 'Verify' and the mention of an optional card, which is insufficient for selecting between overlapping auth-check tools.

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