Asian shares edged up and the euro steadied Thursday after European leaders agreed to boost the region's rescue fund, but their failure to offer a detailed plan to recapitalize banks and reduce Greek debt to a sustainable level may keep gains limited.

Asian credit markets firmed and oil prices rose as strains in the markets eased.

MSCI's broadest index of Asia Pacific shares outside Japan <.MIAPJ0000PUS> rose 0.4 percent to its highest level since Sept. 16, rising about 16 percent from its lows hit on Oct. 4.

The Nikkei <.N225> opened up 0.35 percent.

The blueprint is out, but it's coming in dribs and drabs and not as clear as we thought it will be, said Jonathan Barratt, managing director at Commodity Broking Services, adding that it also did not fully address the issues.

But it's still a step forward and each step keeps optimism intact. But the task ahead is too large to put a deadline on, and if there is a lag, the market will lose its optimism. If there are no concrete measures, it will draw down market prices.

Europe's leaders intend to strengthen their rescue fund to one trillion euros and press Greece's creditors to accept losses of over 50 percent on their bondholdings, but the details of their plan are still not fully formed.

Two options to leverage the bailout fund involved creating a special purpose investment vehicle to tap foreign sovereign and private investors to buy bonds of troubled euro zone countries and using the fund to offer partial guarantees to purchasers of new euro zone debt, according to a draft statement from an emergency euro zone summit on Wednesday obtained by Reuters.

European policymakers also agreed to force banks to raise their capital buffers to 9 percent in core Tier 1 capital, a measure of banks' financial health, by June next year, to protect against losses from any Greek debt restructuring and to contain the region's financial crisis.

In another sign of progress to ease concerns about the Greece debt issues spreading, euro zone leaders will welcome Italy's plans to increase the pension age to 67 but ask for detailed plans.

The euro held up well early in Asia on Thursday with markets, which have all but given up hopes for a comprehensive plan to solve the euro zone debt crisis, seemingly satisfied for now with the sketchy news that is coming out of the EU summit.

The euro was up 0.2 percent above $1.3900, staying away from a six-week high of $1.3959 hit earlier this week.

It's a case of expectations being so low that the risk of a disappointment wasn't that high, said Grant Turley, strategist at ANZ in Sydney.

The dollar touched an fresh all-time low around 75.70 yen on Wednesday, but has since recovered to 76.19.

Commodities rose, with U.S. crude futures gaining more than $1 to $91.13 a barrel on Thursday on news that euro zone leaders plan to boost the region's bailout fund.

Gold extended its gains after rising 1.5 percent to one-month highs on Wednesday, when it notched its longest stretch of gains in over two months.

Gold has been underpinned by safe-haven allure amid uncertainty over the euro zone crisis as well as strong physical demand when prices fall.

Weaker strains on the markets helped narrow the spreads on the iTraxx Asia ex-Japan investment grade index, a gauge for whether investor risk appetite is returning, by five basis points early on Thursday.

Investors' appetite eased for protection in the options market against losses, with the CBOE Volatility index VIX <.VIX> -- a 30-day risk forecast of volatility in the S&P 500 -- falling 29.86 on Wednesday from 32.22 the day before.

MSCI's all-country world equity index <.MIWD00000PUS> rose 0.4 percent on Thursday while U.S. stocks rallied.

Since October 4, when the S&P 500 slumped to intraday levels last seen in September 2010, the benchmark index has surged nearly 15 percent, mostly on hopes for a solution to the debt crisis. But it has still failed to rise above a key technical level of a 61.8 percent retracement of the 2011 decline.

(Additional reporting by Ian Chua in Sydney; Editing by Ron Popeski)